Organic compounds containing carbon and hydrogen in the form of an unsaturated, usually hexagonal ring structure. The compounds can be single ring, or double, triple, or multiple fused rings.
Cytoplasmic proteins that bind certain aryl hydrocarbons, translocate to the nucleus, and activate transcription of particular DNA segments. AH receptors are identified by their high-affinity binding to several carcinogenic or teratogenic environmental chemicals including polycyclic aromatic hydrocarbons found in cigarette smoke and smog, heterocyclic amines found in cooked foods, and halogenated hydrocarbons including dioxins and polychlorinated biphenyls. No endogenous ligand has been identified, but an unknown natural messenger with a role in cell differentiation and development is suspected.
A major group of unsaturated cyclic hydrocarbons containing two or more rings. The vast number of compounds of this important group, derived chiefly from petroleum and coal tar, are rather highly reactive and chemically versatile. The name is due to the strong and not unpleasant odor characteristic of most substances of this nature. (From Hawley's Condensed Chemical Dictionary, 12th ed, p96)
Amino acids containing an aromatic side chain.
Compounds consisting of two or more fused ring structures.
A chemical by-product that results from burning or incinerating chlorinated industrial chemicals and other hydrocarbons. This compound is considered an environmental toxin, and may pose reproductive, as well as, other health risks for animals and humans.
A potent mutagen and carcinogen. It is a public health concern because of its possible effects on industrial workers, as an environmental pollutant, an as a component of tobacco smoke.
A liver microsomal cytochrome P-450 monooxygenase capable of biotransforming xenobiotics such as polycyclic hydrocarbons and halogenated aromatic hydrocarbons into carcinogenic or mutagenic compounds. They have been found in mammals and fish. This enzyme, encoded by CYP1A1 gene, can be measured by using ethoxyresorufin as a substrate for the ethoxyresorufin O-deethylase activity.
Aryl hydrocarbon receptor nuclear translocator is a basic HELIX-LOOP-HELIX MOTIF containing protein that forms a complex with DIOXIN RECEPTOR. The complex binds xenobiotic regulatory elements and activates transcription of a variety of genes including UDP GLUCURONOSYLTRANSFERASE. AhR nuclear translocator is also a subunit of HYPOXIA-INDUCIBLE FACTOR 1.
A group of condensed ring hydrocarbons.
Hydrocarbon compounds with one or more of the hydrogens replaced by CHLORINE.
Elimination of ENVIRONMENTAL POLLUTANTS; PESTICIDES and other waste using living organisms, usually involving intervention of environmental or sanitation engineers.
Four fused benzyl rings with three linear and one angular, that can be viewed as a benzyl-phenanthrenes. Compare with NAPHTHACENES which are four linear rings.
A large group of cytochrome P-450 (heme-thiolate) monooxygenases that complex with NAD(P)H-FLAVIN OXIDOREDUCTASE in numerous mixed-function oxidations of aromatic compounds. They catalyze hydroxylation of a broad spectrum of substrates and are important in the metabolism of steroids, drugs, and toxins such as PHENOBARBITAL, carcinogens, and insecticides.
Naturally occurring complex liquid hydrocarbons which, after distillation, yield combustible fuels, petrochemicals, and lubricants.
The generic name for the group of aliphatic hydrocarbons Cn-H2n+2. They are denoted by the suffix -ane. (Grant & Hackh's Chemical Dictionary, 5th ed)
A class of chemicals that contain an anthracene ring with a naphthalene ring attached to it.
Substances which pollute the soil. Use for soil pollutants in general or for which there is no specific heading.
Chlorinated hydrocarbons containing heteroatoms that are present as contaminants of herbicides. Dioxins are carcinogenic, teratogenic, and mutagenic. They have been banned from use by the FDA.
A carcinogen that is often used in experimental cancer studies.
The products of chemical reactions that result in the addition of extraneous chemical groups to DNA.
Substances or energies, for example heat or light, which when introduced into the air, water, or land threaten life or health of individuals or ECOSYSTEMS.
Substances that increase the risk of NEOPLASMS in humans or animals. Both genotoxic chemicals, which affect DNA directly, and nongenotoxic chemicals, which induce neoplasms by other mechanism, are included.
Organic compounds composed exclusively of carbon and hydrogen. Three or more carbon atoms are arranged in a cyclic structure and they possess aliphatic properties.
Chemical compounds which pollute the water of rivers, streams, lakes, the sea, reservoirs, or other bodies of water.
Complex petroleum hydrocarbons consisting mainly of residues from crude oil distillation. These liquid products include heating oils, stove oils, and furnace oils and are burned to generate energy.
1,2-Benzphenanthrenes. POLYCYCLIC COMPOUNDS obtained from coal tar.
The monitoring of the level of toxins, chemical pollutants, microbial contaminants, or other harmful substances in the environment (soil, air, and water), workplace, or in the bodies of people and animals present in that environment.
A by-product of the destructive distillation of coal used as a topical antieczematic. It is an antipruritic and keratoplastic agent used also in the treatment of psoriasis and other skin conditions. Occupational exposure to soots, tars, and certain mineral oils is known to be carcinogenic according to the Fourth Annual Report on Carcinogens (NTP 85-002, 1985) (Merck Index, 11th ed).
A residue of coal, left after dry (destructive) distillation, used as a fuel.
A widely used industrial solvent.
A greasy substance with a smoky odor and burned taste created by high temperature treatment of BEECH and other WOOD; COAL TAR; or resin of the CREOSOTE BUSH. It contains CRESOLS and POLYCYCLIC AROMATIC HYDROCARBONS which are CARCINOGENS. It has been widely used as wood preservative and in PESTICIDES and had former use medicinally in DISINFECTANTS; LAXATIVES; and DERMATOLOGIC AGENTS.
Volative flammable fuel (liquid hydrocarbons) derived from crude petroleum by processes such as distillation reforming, polymerization, etc.
A concave exterior region on some POLYCYCLIC AROMATIC HYDROCARBONS that have three phenyl rings in a non-linear arrangement.
Release of oil into the environment usually due to human activity.
A family of isomeric, colorless aromatic hydrocarbon liquids, that contain the general formula C6H4(CH3)2. They are produced by the destructive distillation of coal or by the catalytic reforming of petroleum naphthenic fractions. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed)
The chemical alteration of an exogenous substance by or in a biological system. The alteration may inactivate the compound or it may result in the production of an active metabolite of an inactive parent compound. The alterations may be divided into METABOLIC DETOXICATION, PHASE I and METABOLIC DETOXICATION, PHASE II.
Organic compounds composed exclusively of carbon and hydrogen where no carbon atoms join to form a ring structure.
A microanalytical technique combining mass spectrometry and gas chromatography for the qualitative as well as quantitative determinations of compounds.
Carcinogenic substances that are found in the environment.
Tricyclic ethylene-bridged naphthalene derivatives. They are found in petroleum residues and coal tar and used as dye intermediates, in the manufacture of plastics, and in insecticides and fungicides.
Industrial products consisting of a mixture of chlorinated biphenyl congeners and isomers. These compounds are highly lipophilic and tend to accumulate in fat stores of animals. Many of these compounds are considered toxic and potential environmental pollutants.
Toxic, volatile, flammable liquid hydrocarbon byproduct of coal distillation. It is used as an industrial solvent in paints, varnishes, lacquer thinners, gasoline, etc. Benzene causes central nervous system damage acutely and bone marrow damage chronically and is carcinogenic. It was formerly used as parasiticide.
An increase in the rate of synthesis of an enzyme due to the presence of an inducer which acts to derepress the gene responsible for enzyme synthesis.
Any substance in the air which could, if present in high enough concentration, harm humans, animals, vegetation or material. Substances include GASES; PARTICULATE MATTER; and volatile ORGANIC CHEMICALS.
7,8,8a,9a-Tetrahydrobenzo(10,11)chryseno (3,4-b)oxirene-7,8-diol. A benzopyrene derivative with carcinogenic and mutagenic activity.
Chemical agents that increase the rate of genetic mutation by interfering with the function of nucleic acids. A clastogen is a specific mutagen that causes breaks in chromosomes.
Unsaturated hydrocarbons of the type Cn-H2n, indicated by the suffix -ene. (Grant & Hackh's Chemical Dictionary, 5th ed, p408)
Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.
The location of the atoms, groups or ions relative to one another in a molecule, as well as the number, type and location of covalent bonds.
A polyaromatic hydrocarbon inducer of P4501A1 and P4501A2 cytochromes. (Proc Soc Exp Biol Med 1994 Dec:207(3):302-308)
A superfamily of hundreds of closely related HEMEPROTEINS found throughout the phylogenetic spectrum, from animals, plants, fungi, to bacteria. They include numerous complex monooxygenases (MIXED FUNCTION OXYGENASES). In animals, these P-450 enzymes serve two major functions: (1) biosynthesis of steroids, fatty acids, and bile acids; (2) metabolism of endogenous and a wide variety of exogenous substrates, such as toxins and drugs (BIOTRANSFORMATION). They are classified, according to their sequence similarities rather than functions, into CYP gene families (>40% homology) and subfamilies (>59% homology). For example, enzymes from the CYP1, CYP2, and CYP3 gene families are responsible for most drug metabolism.
The relationship between the chemical structure of a compound and its biological or pharmacological activity. Compounds are often classed together because they have structural characteristics in common including shape, size, stereochemical arrangement, and distribution of functional groups.
An essential aromatic amino acid that is a precursor of MELANIN; DOPAMINE; noradrenalin (NOREPINEPHRINE), and THYROXINE.
Oxidases that specifically introduce DIOXYGEN-derived oxygen atoms into a variety of organic molecules.
Two-ring crystalline hydrocarbons isolated from coal tar. They are used as intermediates in chemical synthesis, as insect repellents, fungicides, lubricants, preservatives, and, formerly, as topical antiseptics.
Air pollutants found in the work area. They are usually produced by the specific nature of the occupation.
Organic compounds containing a BENZENE ring attached to a flavone group. Some of these are potent arylhydrocarbon hydroxylase inhibitors. They may also inhibit the binding of NUCLEIC ACIDS to BENZOPYRENES and related compounds. The designation includes all isomers; the 7,8-isomer is most frequently encountered.
The exposure to potentially harmful chemical, physical, or biological agents that occurs as a result of one's occupation.
The presence of bacteria, viruses, and fungi in the soil. This term is not restricted to pathogenic organisms.
A group of compounds derived from ammonia by substituting organic radicals for the hydrogens. (From Grant & Hackh's Chemical Dictionary, 5th ed)
Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.
Gases, fumes, vapors, and odors escaping from the cylinders of a gasoline or diesel internal-combustion engine. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed & Random House Unabridged Dictionary, 2d ed)
Chemical substances that are foreign to the biological system. They include naturally occurring compounds, drugs, environmental agents, carcinogens, insecticides, etc.
Fractionation of a vaporized sample as a consequence of partition between a mobile gaseous phase and a stationary phase held in a column. Two types are gas-solid chromatography, where the fixed phase is a solid, and gas-liquid, in which the stationary phase is a nonvolatile liquid supported on an inert solid matrix.
Spectroscopic method of measuring the magnetic moment of elementary particles such as atomic nuclei, protons or electrons. It is employed in clinical applications such as NMR Tomography (MAGNETIC RESONANCE IMAGING).
A family of diphenylenemethane derivatives.
An essential amino acid that is necessary for normal growth in infants and for NITROGEN balance in adults. It is a precursor of INDOLE ALKALOIDS in plants. It is a precursor of SEROTONIN (hence its use as an antidepressant and sleep aid). It can be a precursor to NIACIN, albeit inefficiently, in mammals.
7,12-Dimethylbenzanthracene. Polycyclic aromatic hydrocarbon found in tobacco smoke that is a potent carcinogen.
A mass of organic or inorganic solid fragmented material, or the solid fragment itself, that comes from the weathering of rock and is carried by, suspended in, or dropped by air, water, or ice. It refers also to a mass that is accumulated by any other natural agent and that forms in layers on the earth's surface, such as sand, gravel, silt, mud, fill, or loess. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed, p1689)
A refined petroleum fraction used as a fuel as well as a solvent.
A body of water located at the southeastern corner of North America. It is bordered by the states to the north of Florida, Alabama, Mississippi, Louisiana, Texas; by five Mexican states to the west: Tamaulipas, Veracruz, Tabasco, Campeche, Yucatan; and by Cuba to the southeast.
A drug-metabolizing, cytochrome P-448 (P-450) enzyme which catalyzes the hydroxylation of benzopyrene to 3-hydroxybenzopyrene in the presence of reduced flavoprotein and molecular oxygen. Also acts on certain anthracene derivatives. An aspect of EC
Non-heme iron-containing enzymes that incorporate two atoms of OXYGEN into the substrate. They are important in biosynthesis of FLAVONOIDS; GIBBERELLINS; and HYOSCYAMINE; and for degradation of AROMATIC HYDROCARBONS.
The rate dynamics in chemical or physical systems.
A cytochrome P450 enzyme subtype that has specificity for relatively planar heteroaromatic small molecules, such as CAFFEINE and ACETAMINOPHEN.
A group of compounds with three aromatic rings joined in linear arrangement.
The characteristic three-dimensional shape of a molecule.
The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.
A species of gram-negative, aerobic bacteria isolated from soil and water as well as clinical specimens. Occasionally it is an opportunistic pathogen.
A natural fuel formed by partial decomposition of vegetable matter under certain environmental conditions.
Tests of chemical substances and physical agents for mutagenic potential. They include microbial, insect, mammalian cell, and whole animal tests.
Adverse effect upon bodies of water (LAKES; RIVERS; seas; groundwater etc.) caused by CHEMICAL WATER POLLUTANTS.
The outer covering of the body composed of the SKIN and the skin appendages, which are the HAIR, the NAILS; and the SEBACEOUS GLANDS and the SWEAT GLANDS and their ducts.
The phenomenon whereby compounds whose molecules have the same number and kind of atoms and the same atomic arrangement, but differ in their spatial relationships. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed)
The exposure to potentially harmful chemical, physical, or biological agents in the environment or to environmental factors that may include ionizing radiation, pathogenic organisms, or toxic chemicals.
A genus of gram-negative, aerobic, rod-shaped bacteria widely distributed in nature. Some species are pathogenic for humans, animals, and plants.
An antiseptic and disinfectant aromatic alcohol.
Liquids that dissolve other substances (solutes), generally solids, without any change in chemical composition, as, water containing sugar. (Grant & Hackh's Chemical Dictionary, 5th ed)
Areas of the earth where hydrocarbon deposits of PETROLEUM and/or NATURAL GAS are located.
Benzopyrenes saturated in any two adjacent positions and substituted with two hydroxyl groups in any position. The majority of these compounds have carcinogenic or mutagenic activity.
A chemical reaction in which an electron is transferred from one molecule to another. The electron-donating molecule is the reducing agent or reductant; the electron-accepting molecule is the oxidizing agent or oxidant. Reducing and oxidizing agents function as conjugate reductant-oxidant pairs or redox pairs (Lehninger, Principles of Biochemistry, 1982, p471).
One of the three domains of life (the others being Eukarya and ARCHAEA), also called Eubacteria. They are unicellular prokaryotic microorganisms which generally possess rigid cell walls, multiply by cell division, and exhibit three principal forms: round or coccal, rodlike or bacillary, and spiral or spirochetal. Bacteria can be classified by their response to OXYGEN: aerobic, anaerobic, or facultatively anaerobic; by the mode by which they obtain their energy: chemotrophy (via chemical reaction) or PHOTOTROPHY (via light reaction); for chemotrophs by their source of chemical energy: CHEMOLITHOTROPHY (from inorganic compounds) or chemoorganotrophy (from organic compounds); and by their source for CARBON; NITROGEN; etc.; HETEROTROPHY (from organic sources) or AUTOTROPHY (from CARBON DIOXIDE). They can also be classified by whether or not they stain (based on the structure of their CELL WALLS) with CRYSTAL VIOLET dye: gram-negative or gram-positive.
The parts of a macromolecule that directly participate in its specific combination with another molecule.
Liquid chromatographic techniques which feature high inlet pressures, high sensitivity, and high speed.
A characteristic feature of enzyme activity in relation to the kind of substrate on which the enzyme or catalytic molecule reacts.
Eight-carbon saturated hydrocarbon group of the methane series. Include isomers and derivatives.
A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances.
Widely distributed enzymes that carry out oxidation-reduction reactions in which one atom of the oxygen molecule is incorporated into the organic substrate; the other oxygen atom is reduced and combined with hydrogen ions to form water. They are also known as monooxygenases or hydroxylases. These reactions require two substrates as reductants for each of the two oxygen atoms. There are different classes of monooxygenases depending on the type of hydrogen-providing cosubstrate (COENZYMES) required in the mixed-function oxidation.
A mixture of liquid hydrocarbons obtained from petroleum. It is used as laxative, lubricant, ointment base, and emollient.
A tri-hydroxy cyclohexene carboxylic acid important in biosynthesis of so many compounds that the shikimate pathway is named after it.
Particles of any solid substance, generally under 30 microns in size, often noted as PM30. There is special concern with PM1 which can get down to PULMONARY ALVEOLI and induce MACROPHAGE ACTIVATION and PHAGOCYTOSIS leading to FOREIGN BODY REACTION and LUNG DISEASES.
Derivatives of BENZOIC ACID. Included under this heading are a broad variety of acid forms, salts, esters, and amides that contain the carboxybenzene structure.
Naphthalene derivatives carrying one or more hydroxyl (-OH) groups at any ring position. They are often used in dyes and pigments, as antioxidants for rubber, fats, and oils, as insecticides, in pharmaceuticals, and in numerous other applications.
Benzoate derivatives substituted by one or more hydroxy groups in any position on the benzene ring.
A genus of gram-negative, aerobic, rod-shaped bacteria characterized by an outer membrane that contains glycosphingolipids but lacks lipopolysaccharide. They have the ability to degrade a broad range of substituted aromatic compounds.
Organic compounds composed exclusively of carbon and hydrogen forming a closed ring that may be either alicyclic or aromatic.
Organic compounds that include a cyclic ether with three ring atoms in their structure. They are commonly used as precursors for POLYMERS such as EPOXY RESINS.
Layers of lipid molecules which are two molecules thick. Bilayer systems are frequently studied as models of biological membranes.
A molecule that binds to another molecule, used especially to refer to a small molecule that binds specifically to a larger molecule, e.g., an antigen binding to an antibody, a hormone or neurotransmitter binding to a receptor, or a substrate or allosteric effector binding to an enzyme. Ligands are also molecules that donate or accept a pair of electrons to form a coordinate covalent bond with the central metal atom of a coordination complex. (From Dorland, 27th ed)
Pheromones that elicit sexual attraction or mating behavior usually in members of the opposite sex in the same species.
The characteristic 3-dimensional shape of a protein, including the secondary, supersecondary (motifs), tertiary (domains) and quaternary structure of the peptide chain. PROTEIN STRUCTURE, QUATERNARY describes the conformation assumed by multimeric proteins (aggregates of more than one polypeptide chain).
Theoretical representations that simulate the behavior or activity of chemical processes or phenomena; includes the use of mathematical equations, computers, and other electronic equipment.
The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.
Family of small, surface-dwelling fish that inhabit fresh and brackish waters, and coastal marine areas.
A bacterial genus of the order ACTINOMYCETALES.
Closed vesicles of fragmented endoplasmic reticulum created when liver cells or tissue are disrupted by homogenization. They may be smooth or rough.
Substances or organisms which pollute the water or bodies of water. Use for water pollutants in general or those for which there is no specific heading.
Placing of a hydroxyl group on a compound in a position where one did not exist before. (Stedman, 26th ed)
Reduction of pharmacologic activity or toxicity of a drug or other foreign substance by a living system, usually by enzymatic action. It includes those metabolic transformations that make the substance more soluble for faster renal excretion.
The science, art, or technology dealing with processes involved in the separation of metals from their ores, the technique of making or compounding the alloys, the techniques of working or heat-treating metals, and the mining of metals. It includes industrial metallurgy as well as metallurgical techniques employed in the preparation and working of metals used in dentistry, with special reference to orthodontic and prosthodontic appliances. (From Jablonski, Dictionary of Dentistry, 1992, p494)
The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.
The facilitation of a chemical reaction by material (catalyst) that is not consumed by the reaction.
Organic compounds that have a relatively high VAPOR PRESSURE at room temperature.
Benzene derivatives that include one or more hydroxyl groups attached to the ring structure.
A clear, odorless, tasteless liquid that is essential for most animal and plant life and is an excellent solvent for many substances. The chemical formula is hydrogen oxide (H2O). (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
High temperature destruction of waste by burning with subsequent reduction to ashes or conversion to an inert mass.
The relationships of groups of organisms as reflected by their genetic makeup.
A transferase that catalyzes the addition of aliphatic, aromatic, or heterocyclic FREE RADICALS as well as EPOXIDES and arene oxides to GLUTATHIONE. Addition takes place at the SULFUR. It also catalyzes the reduction of polyol nitrate by glutathione to polyol and nitrite.
The exposure to potentially harmful chemical, physical, or biological agents by inhaling them.
The art or practice of preparing food. It includes the preparation of special foods for diets in various diseases.
A group of 1,2-benzenediols that contain the general formula R-C6H5O2.
The property of objects that determines the direction of heat flow when they are placed in direct thermal contact. The temperature is the energy of microscopic motions (vibrational and translational) of the particles of atoms.
The presence of bacteria, viruses, and fungi in water. This term is not restricted to pathogenic organisms.
Oils which evaporate readily. The volatile oils occur in aromatic plants, to which they give odor and other characteristics. Most volatile oils consist of a mixture of two or more TERPENES or of a mixture of an eleoptene (the more volatile constituent of a volatile oil) with a stearopten (the more solid constituent). The synonym essential oils refers to the essence of a plant, as its perfume or scent, and not to its indispensability.
Compounds that contain a BENZENE ring fused to a furan ring.
Contamination of the air, bodies of water, or land with substances that are harmful to human health and the environment.
The salinated water of OCEANS AND SEAS that provides habitat for marine organisms.
Ring compounds having atoms other than carbon in their nuclei. (Grant & Hackh's Chemical Dictionary, 5th ed)
A rigorously mathematical analysis of energy relationships (heat, work, temperature, and equilibrium). It describes systems whose states are determined by thermal parameters, such as temperature, in addition to mechanical and electromagnetic parameters. (From Hawley's Condensed Chemical Dictionary, 12th ed)
A class of compounds composed of repeating 5-carbon units of HEMITERPENES.
Organic compounds containing a carbonyl group in the form -CHO.
Methyl, propyl, butyl, and ethyl esters of p-hydroxybenzoic acid. They have been approved by the FDA as antimicrobial agents for foods and pharmaceuticals. (From Hawley's Condensed Chemical Dictionary, 11th ed, p872)
An agent that causes the production of physical defects in the developing embryo.
Organic compounds that generally contain an amino (-NH2) and a carboxyl (-COOH) group. Twenty alpha-amino acids are the subunits which are polymerized to form proteins.
A deoxyribonucleotide polymer that is the primary genetic material of all cells. Eukaryotic and prokaryotic organisms normally contain DNA in a double-stranded state, yet several important biological processes transiently involve single-stranded regions. DNA, which consists of a polysugar-phosphate backbone possessing projections of purines (adenine and guanine) and pyrimidines (thymine and cytosine), forms a double helix that is held together by hydrogen bonds between these purines and pyrimidines (adenine to thymine and guanine to cytosine).
A phase transition from liquid state to gas state, which is affected by Raoult's law. It can be accomplished by fractional distillation.
Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.
Any combustible hydrocarbon deposit formed from the remains of prehistoric organisms. Examples are petroleum, coal, and natural gas.
The restriction of a characteristic behavior, anatomical structure or physical system, such as immune response; metabolic response, or gene or gene variant to the members of one species. It refers to that property which differentiates one species from another but it is also used for phylogenetic levels higher or lower than the species.
Compounds having the nitro group, -NO2, attached to carbon. When attached to nitrogen they are nitramines and attached to oxygen they are NITRATES.
A broad class of substances containing carbon and its derivatives. Many of these chemicals will frequently contain hydrogen with or without oxygen, nitrogen, sulfur, phosphorus, and other elements. They exist in either carbon chain or carbon ring form.
A non-essential amino acid. In animals it is synthesized from PHENYLALANINE. It is also the precursor of EPINEPHRINE; THYROID HORMONES; and melanin.
The simplest saturated hydrocarbon. It is a colorless, flammable gas, slightly soluble in water. It is one of the chief constituents of natural gas and is formed in the decomposition of organic matter. (Grant & Hackh's Chemical Dictionary, 5th ed)
RNA sequences that serve as templates for protein synthesis. Bacterial mRNAs are generally primary transcripts in that they do not require post-transcriptional processing. Eukaryotic mRNA is synthesized in the nucleus and must be exported to the cytoplasm for translation. Most eukaryotic mRNAs have a sequence of polyadenylic acid at the 3' end, referred to as the poly(A) tail. The function of this tail is not known for certain, but it may play a role in the export of mature mRNA from the nucleus as well as in helping stabilize some mRNA molecules by retarding their degradation in the cytoplasm.
A nonmetallic element with atomic symbol C, atomic number 6, and atomic weight [12.0096; 12.0116]. It may occur as several different allotropes including DIAMOND; CHARCOAL; and GRAPHITE; and as SOOT from incompletely burned fuel.
A highly volatile inhalation anesthetic used mainly in short surgical procedures where light anesthesia with good analgesia is required. It is also used as an industrial solvent. Prolonged exposure to high concentrations of the vapor can lead to cardiotoxicity and neurological impairment.
Waste products which threaten life, health, or the environment when improperly treated, stored, transported, disposed of, or otherwise managed.
The relationship between the dose of an administered drug and the response of the organism to the drug.
The study of crystal structure using X-RAY DIFFRACTION techniques. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
Six-carbon saturated hydrocarbon group of the methane series. Include isomers and derivatives. Various polyneuropathies are caused by hexane poisoning.
The thermodynamic interaction between a substance and WATER.
A family of DNA-binding transcription factors that contain a basic HELIX-LOOP-HELIX MOTIF.
The scattering of x-rays by matter, especially crystals, with accompanying variation in intensity due to interference effects. Analysis of the crystal structure of materials is performed by passing x-rays through them and registering the diffraction image of the rays (CRYSTALLOGRAPHY, X-RAY). (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
Constituent of 30S subunit prokaryotic ribosomes containing 1600 nucleotides and 21 proteins. 16S rRNA is involved in initiation of polypeptide synthesis.
Hydrocarbon-rich byproducts from the non-fossilized BIOMASS that are combusted to generate energy as opposed to fossilized hydrocarbon deposits (FOSSIL FUELS).
Insects of the family Formicidae, very common and widespread, probably the most successful of all the insect groups. All ants are social insects, and most colonies contain three castes, queens, males, and workers. Their habits are often very elaborate and a great many studies have been made of ant behavior. Ants produce a number of secretions that function in offense, defense, and communication. (From Borror, et al., An Introduction to the Study of Insects, 4th ed, p676)
A multistage process that includes cloning, physical mapping, subcloning, determination of the DNA SEQUENCE, and information analysis.
A basic science concerned with the composition, structure, and properties of matter; and the reactions that occur between substances and the associated energy exchange.
The class of all enzymes catalyzing oxidoreduction reactions. The substrate that is oxidized is regarded as a hydrogen donor. The systematic name is based on donor:acceptor oxidoreductase. The recommended name will be dehydrogenase, wherever this is possible; as an alternative, reductase can be used. Oxidase is only used in cases where O2 is the acceptor. (Enzyme Nomenclature, 1992, p9)
The degree of similarity between sequences of amino acids. This information is useful for the analyzing genetic relatedness of proteins and species.
The contamination of indoor air.
Agents that modify interfacial tension of water; usually substances that have one lipophilic and one hydrophilic group in the molecule; includes soaps, detergents, emulsifiers, dispersing and wetting agents, and several groups of antiseptics.
Chromatography on thin layers of adsorbents rather than in columns. The adsorbent can be alumina, silica gel, silicates, charcoals, or cellulose. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
The industry concerned with the removal of raw materials from the Earth's crust and with their conversion into refined products.
A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.
Changing an open-chain hydrocarbon to a closed ring. (McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed)
A drug-metabolizing enzyme found in the hepatic, placental and intestinal microsomes that metabolizes 7-alkoxycoumarin to 7-hydroxycoumarin. The enzyme is cytochrome P-450- dependent.
Determination of the spectra of ultraviolet absorption by specific molecules in gases or liquids, for example Cl2, SO2, NO2, CS2, ozone, mercury vapor, and various unsaturated compounds. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
An analytical method used in determining the identity of a chemical based on its mass using mass analyzers/mass spectrometers.
A solventless sample preparation method, invented in 1989, that uses a fused silica fiber which is coated with a stationary phase. It is used for sample cleanup before using other analytical methods.
Chemical substances, excreted by an organism into the environment, that elicit behavioral or physiological responses from other organisms of the same species. Perception of these chemical signals may be olfactory or by contact.
Proteins found in any species of bacterium.
The composition, conformation, and properties of atoms and molecules, and their reaction and interaction processes.
Enzymes that catalyze reversibly the formation of an epoxide or arene oxide from a glycol or aromatic diol, respectively.
Hydrocarbon rings which contain two ketone moieties in any position. They can be substituted in any position except at the ketone groups.
The level of protein structure in which regular hydrogen-bond interactions within contiguous stretches of polypeptide chain give rise to alpha helices, beta strands (which align to form beta sheets) or other types of coils. This is the first folding level of protein conformation.
A low-energy attractive force between hydrogen and another element. It plays a major role in determining the properties of water, proteins, and other compounds.
An enzyme that catalyzes the formation of 7-phospho-2-keto-3-deoxy-D-arabinoheptonate from phosphoenolpyruvate and D-erythrose-4-phosphate. It is one of the first enzymes in the biosynthesis of TYROSINE and PHENYLALANINE. This enzyme was formerly listed as EC
Genetically engineered MUTAGENESIS at a specific site in the DNA molecule that introduces a base substitution, or an insertion or deletion.

Contrasting effects of a nonionic surfactant on the biotransformation of polycyclic aromatic hydrocarbons to cis-dihydrodiols by soil bacteria. (1/332)

The biotransformation of the polycyclic aromatic hydrocarbons (PAHs) naphthalene and phenanthrene was investigated by using two dioxygenase-expressing bacteria, Pseudomonas sp. strain 9816/11 and Sphingomonas yanoikuyae B8/36, under conditions which facilitate mass-transfer limited substrate oxidation. Both of these strains are mutants that accumulate cis-dihydrodiol metabolites under the reaction conditions used. The effects of the nonpolar solvent 2,2,4, 4,6,8,8-heptamethylnonane (HMN) and the nonionic surfactant Triton X-100 on the rate of accumulation of these metabolites were determined. HMN increased the rate of accumulation of metabolites for both microorganisms, with both substrates. The enhancement effect was most noticeable with phenanthrene, which has a lower aqueous solubility than naphthalene. Triton X-100 increased the rate of oxidation of the PAHs with strain 9816/11 with the effect being most noticeable when phenanthrene was used as a substrate. However, the surfactant inhibited the biotransformation of both naphthalene and phenanthrene with strain B8/36 under the same conditions. The observation that a nonionic surfactant could have such contrasting effects on PAH oxidation by different bacteria, which are known to be important for the degradation of these compounds in the environment, may explain why previous research on the application of the surfactants to PAH bioremediation has yielded inconclusive results. The surfactant inhibited growth of the wild-type strain S. yanoikuyae B1 on aromatic compounds but did not inhibit B8/36 dioxygenase enzyme activity in vitro.  (+info)

Aromatic ring cleavage of a non-phenolic beta-O-4 lignin model dimer by laccase of Trametes versicolor in the presence of 1-hydroxybenzotriazole. (2/332)

The novel cleavage products, 2,3-dihydroxy-1-(4-ethoxy-3-methoxyphenyl)-1-formyloxypropane (II) and 1-(4-ethoxy-3-methoxyphenyl)-1,2,3-trihydroxypropane-2,3-cyclic carbonate (III) were identified as products of a non-phenolic beta-O-4 lignin model dimer, 1,3-dihydroxy-2-(2,6-dimethoxylphenoxy)-1-(4-ethoxy-3-methoxypheny l)propane (I), by a Trametes versicolor laccase in the presence of 1-hydroxybenzotriazole (1-HBT). An isotopic experiment with a 13C-labeled lignin model dimer, 1,3-dihydroxy-2-(2,6-[U-ring-13C] dimethoxyphenoxy)-1-(4-ethoxy-3-methoxyphenyl)propane (I-13C) indicated that the formyl and carbonate carbons of products II and III were derived from the beta-phenoxy group of beta-O-4 lignin model dimer I as aromatic ring cleavage fragments. These results show that the laccase-1-HBT couple could catalyze the aromatic ring cleavage of non-phenolic beta-O-4 lignin model dimer in addition to the beta-ether cleavage, Calpha-Cbeta cleavage, and Calpha-oxidation.  (+info)

Microbiology of the oil fly, Helaeomyia petrolei. (3/332)

Helaeomyia petrolei larvae isolated from the asphalt seeps of Rancho La Brea in Los Angeles, Calif., were examined for microbial gut contents. Standard counts on Luria-Bertani, MacConkey, and blood agar plates indicated ca. 2 x 10(5) heterotrophic bacteria per larva. The culturable bacteria represented 15 to 20% of the total population as determined by acridine orange staining. The gut itself contained large amounts of the oil, had no observable ceca, and maintained a slightly acidic pH of 6.3 to 6.5. Despite the ingestion of large amounts of potentially toxic asphalt by the larvae, their guts sustained the growth of 100 to 1,000 times more bacteria than did free oil. All of the bacteria isolated were nonsporeformers and gram negative. Fourteen isolates were chosen based on representative colony morphologies and were identified by using the Enterotube II and API 20E systems and fatty acid analysis. Of the 14 isolates, 9 were identified as Providencia rettgeri and 3 were likely Acinetobacter isolates. No evidence was found that the isolates grew on or derived nutrients from the asphalt itself or that they played an essential role in insect development. Regardless, any bacteria found in the oil fly larval gut are likely to exhibit pronounced solvent tolerance and may be a future source of industrially useful, solvent-tolerant enzymes.  (+info)

Effect of organic solvents on the yield of solvent-tolerant Pseudomonas putida S12. (4/332)

Solvent-tolerant microorganisms are useful in biotransformations with whole cells in two-phase solvent-water systems. The results presented here describe the effects that organic solvents have on the growth of these organisms. The maximal growth rate of Pseudomonas putida S12, 0.8 h-1, was not affected by toluene in batch cultures, but in chemostat cultures the solvent decreased the maximal growth rate by nearly 50%. Toluene, ethylbenzene, propylbenzene, xylene, hexane, and cyclohexane reduced the biomass yield, and this effect depended on the concentration of the solvent in the bacterial membrane and not on its chemical structure. The dose response to solvents in terms of yield was linear up to an approximately 200 mM concentration of solvent in the bacterial membrane, both in the wild type and in a mutant lacking an active efflux system for toluene. Above this critical concentration the yield of the wild type remained constant at 0.2 g of protein/g of glucose with increasing concentrations of toluene. The reduction of the yield in the presence of solvents is due to a maintenance higher by a factor of three or four as well as to a decrease of the maximum growth yield by 33%. Therefore, energy-consuming adaptation processes as well as the uncoupling effect of the solvents reduce the yield of the tolerant cells.  (+info)

Enhancement of solubilization and biodegradation of polyaromatic hydrocarbons by the bioemulsifier alasan. (5/332)

Alasan, a high-molecular-weight bioemulsifier complex of an anionic polysaccharide and proteins that is produced by Acinetobacter radioresistens KA53 (S. Navon-Venezia, Z. Zosim, A. Gottlieb, R. Legmann, S. Carmeli, E. Z. Ron, and E. Rosenberg, Appl. Environ. Microbiol. 61:3240-3244, 1995), enhanced the aqueous solubility and biodegradation rates of polyaromatic hydrocarbons (PAHs). In the presence of 500 microg of alasan ml-1, the apparent aqueous solubilities of phenanthrene, fluoranthene, and pyrene were increased 6.6-, 25.7-, and 19.8-fold, respectively. Physicochemical characterization of the solubilization activity suggested that alasan solubilizes PAHs by a physical interaction, most likely of a hydrophobic nature, and that this interaction is slowly reversible. Moreover, the increase in apparent aqueous solubility of PAHs does not depend on the conformation of alasan and is not affected by the formation of multimolecular aggregates of alasan above its saturation concentration. The presence of alasan more than doubled the rate of [14C]fluoranthene mineralization and significantly increased the rate of [14C]phenanthrene mineralization by Sphingomonas paucimobilis EPA505. The results suggest that alasan-enhanced solubility of hydrophobic compounds has potential applications in bioremediation.  (+info)

Taxonomic characterization of denitrifying bacteria that degrade aromatic compounds and description of Azoarcus toluvorans sp. nov. and Azoarcus toluclasticus sp. nov. (6/332)

A taxonomic characterization of twenty-one strains capable of degrading aromatic compounds under denitrifying conditions, isolated from ten different geographical locations, was performed on the basis of general morphological and physiological characteristics, cellular fatty acids, DNA base composition, small ribosomal (16S) subunit DNA sequences, whole-cell protein patterns and genomic DNA fragmentation analysis, in addition to DNA similarity estimations using hybridization methods. The collection of strains was subdivided into a number of different groups. A first group, consisting of four strains, could be assigned to the previously described species Azoarcus tolulyticus. A second group (five strains) had DNA which reannealed highly to that of strains of the first group, and it is considered to represent a genomovar of A. tolulyticus. The third and fourth groups, composed of a total of five strains, represent a new species of Azoarcus, Azoarcus toluclasticus (group 3) and a genomovar of this species (group 4), respectively. Finally, the fifth group, with two strains, corresponds to another new species of the genus Azoarcus, Azoarcus toluvorans. In addition to these five groups, the collection includes five individual strains perhaps representing as many different new species. The above classification is partially consistent with the results of approaches other than DNA-DNA hybridization (electrophoretic patterns of whole-cell proteins and of the fragments obtained after digestion of total DNA with infrequently cutting restriction enzymes). On the other hand, no correlation of these groupings was found in terms of the cellular fatty acid composition. It is also unfortunate that no simple sets of easily determinable phenotypic properties could be defined as being characteristic of each of the groups.  (+info)

Clostridium methoxybenzovorans sp. nov., a new aromatic o-demethylating homoacetogen from an olive mill wastewater treatment digester. (7/332)

A strictly anaerobic, spore-forming bacterium (3.0-5.0 x 0.4-0.8 microns), designated strain SR3T (T = type strain), which stained Gram-positive and possessed a Gram-positive type cell wall was isolated from a methanogenic pilot-scale digester fed with olive mill wastewater (Sfax, Tunisia). It utilized a number of carbohydrates (glucose, fructose, sorbose, galactose, myo-inositol, sucrose, lactose, cellobiose), organic compounds (lactate, betaine, sarcosine, dimethylglycine, methanethiol, dimethylsulfide), alcohol (methanol) and all methoxylated aromatic compounds only in the presence of yeast extract (0.1%). The end products from carbohydrate fermentation were H2, CO2, formate, acetate and ethanol, that from lactate was methanol, those from methoxylated aromatics were acetate and butyrate, and that from betaine, sarcosine, dimethylglycine, methanethiol and dimethylsulfide was only acetate. Strain SR3T was non-motile, had a G+C content of 44 mol% and grew optimally at 37 degrees C and pH 7.4 on a glucose-containing medium. Phylogenetically, the closest relatives of strain SR3T were the non-methoxylated aromatic-degrading Clostridium xylanolyticum, Clostridium aerotolerans, Clostridium sphenoides and Clostridium celerecrescens (mean similarity of 98%). On the basis of the phenotypic, genotypic and phylogenetic characteristics of the isolate, it is proposed to designate strain SR3T as Clostridium methoxybenzovorans sp. nov. The type strain is SR3T (= DSM 12182T).  (+info)

The difference between the CB(1) and CB(2) cannabinoid receptors at position 5.46 is crucial for the selectivity of WIN55212-2 for CB(2). (8/332)

It has been reported that WIN55212-2, a prototypic aminoalkylindole, has higher affinity for CB(2) than for CB(1). To explain the selectivity of WIN55212-2 for CB(2), molecular modeling studies were performed to probe the interacting sites between WIN55212-2 and cannabinoid receptors. In TMH5 the position 5.46 is a Phe in CB(2) versus a Val in CB(1). Docking of WIN55212-2 into the models of CB(1) and CB(2) predicts that F5.46 will result in a greater aromatic stacking of CB(2) with WIN55212-2. Using site-directed mutagenesis, this hypothesis was tested by exchanging the amino acids at position 5.46 between CB(1) and CB(2). Two mutations, including a Phe to Val mutation at the position 5.46 in CB(2) (CB2F5. 46V), and a corresponding Val to Phe mutation at the position 5.46 in CB(1) (CB(1)V5.46F), were made. The mutant receptors were transfected into 293 cells, and stable cell lines expressing similar numbers of receptors as wild-type receptors were chosen for additional ligand binding and cAMP accumulation studies. In ligand- binding assays, the CB(2)F5.46V mutation decreased the affinity of WIN55212-2 for CB(2) by 14-fold. In contrast, the CB(1)V5.46F mutation increased the affinity of WIN55212-2 for CB(1) by 12-fold. However, these mutations did not change the affinity of HU-210, CP-55940, and anandamide for CB(1) and CB(2). In cAMP accumulation assays, the changes in EC(50) values of WIN55212-2 were consistent with the changes in its binding affinity caused by the mutations. These results strongly support the hypothesis that the selectivity of WIN55212-2 for CB(2) over CB(1) is attributable to the change from Val in CB(1) at position 5.46 to Phe in CB(2).  (+info)

Substituted heteroaromatic compounds, and in particular substituted bicyclic heteroaromatic compounds in which one ring is a pyridine or pyrimidine of formula (I) are protein tyrosine kinase inhibitors. The compounds are described as are methods for their preparation, pharmaceutical compositions including such compounds and their use in medicine, for example in the treatment of cancer and psoriasis.
Discovering the Mechanism of H2 Adsorption on Aromatic Carbon Nanostructures to Develop Adsorbents for Vehicular Applications - Volume 837 - A. C. Dillon, J. L. Blackburn, P. A. Parilla, Y. Zhao, Y-H. Kim, S. B. Zhang, A. H. Mahan, J. L. Alleman, K. M. Jones, K. E. H. Gilbert, M. J Heben
The transformation of benzene and a series of alkylbenzenes was studied in anoxic groundwater of a shallow glacial-outwash aquifer near Bemidji, Minnesota, U.S.A. Monoaromatic hydrocarbons, the most water-soluble components of crude oil, were transported downgradient of an oil spill, forming a plume of contaminated groundwater. Organic acids that were not original components of the oil were identified in the anoxic groundwater. The highest concentrations of these oxidized organic compounds were found in the anoxic plume where a decrease in concentrations of structurally related alkylbenzenes was observed. These results suggest that biological transformation of benzene and alkylbenzenes to organic acid intermediates may be an important attenuation process in anoxic environments. The transformation of a complex mixture of hydrocarbons to a series of corresponding oxidation products in an anoxic subsurface environment provides new insight into in situ anaerobic degradation processes. ?? 1990 Springer
The trophic transfer of monoaromatic hydrocarbons to predatory organisms feeding upon contaminated marine animals is not well reported within the scientific literature. Branched alkylbenzenes (BABs) unresolved by gas chromatography have been reported to be principal toxic components of bioaccumulated hydrocarbons in the tissues of some wild mussel, Mytllus edulis, populations with poor health status. Mussels, M. edulis, contaminated with a commercial mixture of BABs were fed to shore crabs, Garcinus maenas, for 7 d, and effects upon the behavior, heart rate, hemolymph cellular viability, and immune response of the crabs were assessed. Accumulation of BABs in crab midgut gland tissue was quantified by gas chromatography-mass spectrometry, and the presence of BABs in crab urine was detected spectrophotometrically using ultraviolet fluorescence spectroscopy. Analysis of crab tissues and urine revealed a proportion of the BABs was transferred from the mussel tissues to the crabs, but the majority ...
In organic chemistry, the term aromaticity is used to describe a cyclic (ring-shaped), planar (flat) molecule with a ring of resonance bonds that exhibits more stability than other geometric or connective arrangements with the same set of atoms. Aromatic molecules are very stable, and do not break apart easily to react with other substances. Organic compounds that are not aromatic are classified as aliphatic compounds-they might be cyclic, but only aromatic rings have special stability (low reactivity). Since the most common aromatic compounds are derivatives of benzene (an aromatic hydrocarbon common in petroleum and its distillates), the word aromatic occasionally refers informally to benzene derivatives, and so it was first defined. Nevertheless, many non-benzene aromatic compounds exist. In living organisms, for example, the most common aromatic rings are the double-ringed bases in RNA and DNA. An aromatic functional group or other substituent is called an aryl group. The earliest use of ...
TY - PAT. T1 - Heteroaromatic compounds and their use as dopamine D1 ligands. AU - Allen, John. PY - 2017/4/11. Y1 - 2017/4/11. UR -,617,275%2526OS%3D9,617,275%2526RS%3D9,617,275&PageNum=&Rtype=&SectionNum=&idkey=NONE&Input=View+first+page. M3 - Patent. M1 - 9,617,275 B2. PB - United States Patent Office. ER - ...
This 1954 book was the first to be devoted to the fundamental properties of the aromatic compounds as a whole. It describes the experimental and theoretical attempts to explain their structure and discusses their characteristic properties and the mechanism of their reactions. Heterocyclic compounds are included in Dr Badgers survey. Aromatic compounds are characterised by their cyclic molecular structure, their high degree of unsaturation and their stability. Coal tar is the chief source of aromatic compounds, but they are also made from crude oil and can be produced synthetically. Nearly all dyestuffs are aromatic, as are most of the common drugs and explosives. The book addressed itself primarily to graduates and final-year undergraduates. It was also of interest to research chemists in the dyestuffs, pharmaceutical and explosives industries. As some complex aromatic compounds produce cancer on the skin of laboratory animals, cancer research workers will also have found it relevant.. ...
Aromatic compounds are cyclic, fully conjugated, planar molecules with a specific number of π electrons. This thesis elaborates aromatic compounds and their characteristic reactions. Phenols and quinones represent a class of organic compounds with various role. Phenols are aromatic compounds containing a hydroxy group bonded to an aromatic ring, while quinones are derivated from aromatic compounds, but arent aromatic compounds themselves. Quinones represent a group of non-aromatic conjugated cyclohexadienones and therefore are observed as α,β-unsaturated compounds. This thesis also elaborates phenols and quinones, their reactions, synthesis and uses, but also their biological importance ...
Reviews M. Ste?pien?, L. Latos-Graz?yn?ski, and N. Sprutta DOI: 10.1002/anie.201003353 Porphyrinoids Figure Eights, Mbius Bands, and More: Conformation and Aromaticity of Porphyrinoids** Marcin Ste?pien?,* Natasza Sprutta, and Lechos?aw Latos-Graz?yn?ski* Keywords: aromaticity и chemical topology и conformational analysis и NMR spectroscopy и porphyrinoids Dedicated to Professor Alan L. Balch on the occasion of his 70th birthday Angewandte Chemie 4288 2011 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim Angew. Chem. Int. Ed. 2011, 50, 4288 ? 4340 Porphyrinoids The aromatic character of porphyrins, which has significant chemical and biological consequences, can be substantially altered by judicious modifications of the parent ring system. Expansion of the macrocycle, which is achieved by introducing additional subunits, usually increases the so-called free curvature of the ring, leading to larger angular strain. This strain is reduced by a variety of conformational changes, most ...
Aromaticity means cyclic planar conjugated and Huckels rule for a stable pi system. This includes multi-resonating systems, charged and heterocyclic aromatic compounds.
What is the reason that aromatic compounds are more stable than other cyclic compounds ? Please provide answer in reference to MOT theory ...
Landolt-Börnstein - Group II Molecules and Radicals | Volume 26E2 | Book DOI: 10.1007/978-3-540-87641-0 | SpringerMaterials 2009
Polymetalated aromatic compounds are of great interest because of their intermediate roles in many organic transformations. However, they are elusive and synthetically challenging. In this study, a dynamic coordination capsule constructed by a flexible macrocycle and silver(i) ions is applied to trigger one-
Xenobiotics biodegradation Aromatics degradation M00569 Catechol meta-cleavage, catechol => acetyl-CoA / 4-methylcatechol => propanoyl-CoA [PATH:T31030_00362 T31030_00622 T31030_01220 T31030_01100 T31030_01120 ...
If you have a question about this talk, please contact Lingtao Kong.. Aromatic oligomers constitute a distinct and promising class of synthetic foldamers - oligomers that adopt stable folded conformations. Single helical structures are, to a large extent, predictable, show unprecedented conformational stability, and represent convenient building blocks to elaborate synthetic, very large (protein-sized) folded architectures. This lecture will give an overview of our current efforts to design abiotic tertiary structures based on aromatic scaffolds,[1] to prepare and select (as opposed to design) aromatic foldamer-peptide hybrid architectures,[2,3] and to use aromatic foldamers to recognize sizeable protein surfaces.[4,5]. References:. [1] S. De et al., Designing cooperatively folded abiotic uni- and multimolecular helix bundles, Nat. Chem. 2018, 10, 51. [2] J. M. Rogers, S. Kwon et al. Ribosomal synthesis and folding of peptide-helical aromatic foldamer hybrids, Nat. Chem. 2018, 10, 405. [3] M. ...
Theoretical investigations regarding the aromatic character of naphthalene, quinoline and isoquinoline have been performed. Local aromaticity indices like HOMA, NICS, PDI and FLU have been computed, in order to establish the influence of the substitution of a CH group with an isovalent N atom. Also, the gas-phase enthalpies of deprotonation of naphthalene, quinoline and isoquinoline have been computed; results were compared with the experimental enthalpy of deprotonation of benzene. ...
The name aromatic comes from the characteristic odor or aroma of benzene-like compounds. Aromatic compounds are : The structure must be cyclic and contain some ...
The main focus of this thesis is on the aromaticity of the ground state and electronically excited states of π-conjugated molecules and polymers, as well as how aromaticity is connected to their properties.. The electronic structures of polybenzenoid hydrocarbons (PBHs) were explored through density functional theory (DFT) calculations and the π-component of the electron localization function (ELFπ). The study revealed how the π-electronic structure is influenced by the fusion of double bonds or benzene rings to the PBHs. We also demonstrated that the π-electrons of benzene extend to accommodate as much aromaticity as possible when bond length distorted. The aromatic chameleon property displayed by fulvenes, isobenzofulvenes, fulvalenes, bis(fulvene)s, and polyfulvenes were investigated using DFT calculations. The tria-, penta-, and heptafulvenes were shown to possess ionization energies and electron affinities which can be tuned extensively by substitution, some of which even outperform ...
The RRM folds into a αβ structure with β1α1 β2 β 3α2 β4 with one four stranded antiparallel β-sheet and two alpha helices that are positioned against the sheet. More than 30 RRM structures have been determined by X-ray crystallography and NMR and these structures show a surprising amount of variation in the arrangement of the alpha helices and beta sheets.. An archetype example of RRM binding structure is the DNA-protein complex formed by hnRNPA1, which can bind both DNA and RNA. In this DNA-RNPA1 complex, two deoxynucleotides, A209 and G210 stack on aromatic rings located on beta 1 strands and cause rearrangement of the nucleic acid on the beta sheet in which the 5 end is on the first half of the sheet and the 3 is on the second half. A third aromatic residue interacts with hydrophobically with carbohydrate rings of A209 and G210 and a positively charged side chain of the RNP forms a salt bridge with the phosphate between A209 and G210.. ...
***New Barriques available - staves sorted and selected by NIR profiling ***New Puncheons (500 L) available ***New 1000 Litre Experience forkliftable available ***New 1000 Litre horizontal available ***New 25 hl Conical closed vats available From the premier large format cooperage in the world - Garbellotto - who supply most of the top European wineries and specialize in large format cooperage. Theyve been at it for almost 300 years, and no-one makes better, or stronger tonneaux than they do, from 225 barriques through to 25,000 litre vats. Garbellotto have developed and patented an NIR (Near Infra-Red) technology (backed by decades of wet chemistry cross-referencing) to sort staves based on aromatic precursors. No other cooperage is currently capable of selecting staves for barrels this way. The cooperage seasons the oak for 3 years, then in the production phase for making a barrel they NIR scan each stave to determine what the aromatic pre-cursors of the stave wood are, and they sort
Salah, S. M., Meisenheimer, J. D., Rao, R., Peda, J. D., Wallace, D. P., Foster, D., Li, X., Li, X., Zhou, X., Vallejo, J. A., Wacker, M. J., Fields, T. A. & Swenson-Fields, K. I., Jan 1 2019, In : American Journal of Physiology - Renal Physiology. 317, 2, p. F343-F360. Research output: Contribution to journal › Article ...
Row 10: Bergen - Cathey - Chapman - Gamble - Todd Graham - Don Smith - ? - Polly - McCloskey - Row 9: Blitch - Secord - Jim Ryan - Wing - ? - Row 8: ? - Matuszak - Wayne Smith - ? - Fleeger - Lynn - Joe Franklin - Charlie Johnson - Gunderson - Row 7: Regnier - ? - Reed - Stone - Herren - Weaver - Matteson - Hayes - ? - Enslow - Cliff Jones - ? - Reid - Feagin - Row 6: Wargowsky - Lichtenberg - Sanderson - Baker - Dienst - McCulla - Schick - Ludwig - Soper - Bean - Shideler - Lenio - Pirkey - Row 5: Goldstein - Fralen - Le Cates - Meisenheimer - Wheeler - Horst - Whittaker ? - Cardillo - Page - Newton - Prater - Lucas - Row 4: ? - Sloan - Traut - Rich Miller - Hoeferkamp - Heye - ? - West - Bill Graham - Row 3: Andrews - Perkins - Gay - Pace - Olvey - Strati - Dugan - Jackson - Whtitaker ? - Ralph Henry - Gallup - Murray - Ewing - Fikaris - Row 2: Hornbarger - Al Edwards - Robinson - ? - Thorsen - Dickson - Vitty - Tom Phillips - Bill Anderson - Giddings - Jacobs - Dryer - Row 1: Bazilwich - ...
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Hi Pascal, for the CDK, we decided that we want it to behave like a Lego construction set. Each of the components should only do the minimal promised work, which gives maximum flexibility in wiring things together as you like them. In your example, you would always need to do aromaticity detection (using some or so) to do the detection before doing the Murcko stuff. The reasoning in this case, although a bit artificial in this case, might be that some dude somewhere might want to do the Murcko fragmentation on the Kekule-Representations instead of the aromaticity-marked one and if we do the aromaticity detection *inside* the Murcko fragmentation, we hinder him to do so. As usual, a note on this behaviour should go into the Javadoc documentation :-) Hope that helps, Chris On 30 Sep 2010, at 10:08, Pascal Muller wrote: , Hi, , , I would like to generate Murcko framework for my library (a big Zinc , subset). But for now, Im just trying to do it for a few smiles ...
Page contains details about heteroaromatic host-based organic electroluminescent element . It has composition images, properties, Characterization methods, synthesis, applications and reference articles :
Correct Answer: D.. Aromatic compounds follow four rules: (1) They are conjugated-there needs to one p orbital from each atom in the ring, so each atom must be either sp2 or sp hybridized; 2) They are cyclic: linear systems are not aromatic; 3) They are planar: there is good overlap/interaction between p orbitals; 4) they follow the The Huckel Rule-4n+2 pi electrons in the cyclic conjugated pi system (n = 0, 1, 2, 3 etc ...
Author(s): Fatayer, Shadi; Coppola, Alysha I; Schulz, Fabian; Walker, Brett D; Broek, Taylor A; Meyer, Gerhard; Druffel, Ellen RM; McCarthy, Matthew; Gross, Leo
To facilitate this reaction, the aromaticity of the pyridines was weakened by forming n-iminopyridium ylides. Antes del amanecer del 9 de marzo de , un grupo de
Natures Own all natural terpenes are an effects-rich terpenes base combined with a variety of other aromatic compounds.The Natures Own proprietary blend of our all natural terpenes mix.
The invention provides methods for substituting polyaromatic hydrocarbons or polyheterocyclic compounds with perfluoroalkyl groups. The methods can include heating a polyaromatic hydrocarbon substrate or a polyheterocyclic compound substrate in the presence of a perfluoroalkyl iodide, typically in a closed system, wherein the heating is sufficient to bring both the polyaromatic hydrocarbons or polyheterocyclic compound, and the perfluoroalkyl iodide, into the gas phase, thereby allowing the substrate to react with the perfluoroalkyl iodide in the gas phase to form polyaromatic hydrocarbons or polyheterocyclic compounds having one or more perfluoroalkyl substituents. The methods allow for the creation of versatile libraries of novel perfluoroalkyl-containing derivatives that can serve as important building blocks and active components in biomedical, electronic, and materials applications.
BACKGROUND: Groundwater and subsurface environments contaminated with aromatic compounds can be remediated in situ by Geobacter species that couple oxidation of these compounds to reduction of Fe(III)-oxides. Geobacter metallireducens metabolizes many aromatic compounds, but the enzymes involved are not well known.. RESULTS: The complete G. metallireducens genome contained a 300 kb island predicted to encode enzymes for the degradation of phenol, p-cresol, 4-hydroxybenzaldehyde, 4-hydroxybenzoate, benzyl alcohol, benzaldehyde, and benzoate. Toluene degradation genes were encoded in a separate region. None of these genes was found in closely related species that cannot degrade aromatic compounds. Abundant transposons and phage-like genes in the island suggest mobility, but nucleotide composition and lack of synteny with other species do not suggest a recent transfer. The inferred degradation pathways are similar to those in species that anaerobically oxidize aromatic compounds with nitrate as an ...
Pseudomonas putida CSV86 utilizes glucose, naphthalene, methylnaphthalene, benzyl alcohol and benzoate as the sole source of carbon and energy. Compared with glucose, cells grew faster on aromatic compounds as well as on organic acids. The organism failed to grow on gluconate, 2-ketogluconate, fructose and mannitol. Whole-cell oxygen uptake, enzyme activity and metabolic studies suggest that in strain CSV86 glucose utilization is exclusively by the intracellular phosphorylative pathway, while in Stenotrophomonas maltophilia CSV89 and P. putida KT2442 glucose is metabolized by both direct oxidative and indirect phosphorylative pathways. Cells grown on glucose showed five- to sixfold higher activity of glucose-6-phosphate dehydrogenase compared with cells grown on aromatic compounds or organic acids as the carbon source. Study of [C-14]glucose uptake by whole cells indicates that the glucose is taken up by active transport. Metabolic and transport studies clearly demonstrate that glucose ...
TY - JOUR. T1 - Mass transfer of polynuclear aromatic hydrocarbons from complex DNAPL mixtures. AU - Mukherji, Suparna. AU - Peters, Catherine Anne. AU - Weber, Walter J.. PY - 1997/2/1. Y1 - 1997/2/1. N2 - Parameters governing the rates of mass transfer of the individual components of four synthetic dense non-aqueous phase liquid (DNAPL) mixtures into the aqueous phase were evaluated. The DNAPL mixtures, composed of toluene and eight polynuclear aromatic hydrocarbons (PAHs), were designed to serve as models for coal tars and creosotes. The reactor employed provided a relatively stable interface between internally mixed but segregated aqueous and DNAPL phases. Two parameters, the aqueous phase concentration at equilibrium and the overall film mass transfer coefficient, were quantified by simulating aqueous concentration profiles with a mass-transfer-limited rate model using a statistical parameter search and data fitting routine. DNAPL phase activity coefficient values for the various compounds ...
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The latest report on Aromatic Hydrocarbon Resins Industry Market divided by product type, applications, industry verticals and research regions presents growth perspectives, and comprehensive market statistics. An up-to-date Aromatic Hydrocarbon Resins market analysis projects the demand, supply, market share and revenue analysis from 2020-2026. Various Aromatic Hydrocarbon Resins industry verticals are featured in the study along with competitive industry scenario. A lucrative product overview, growth enhancers, market risks, industry plans and policies are covered. The Aromatic Hydrocarbon Resins research highlights the information related to market dynamics and authentic numbers fueling the growth and Aromatic Hydrocarbon Resins industry development on a global scale.. The Aromatic Hydrocarbon Resins report is well-structured to portray Aromatic Hydrocarbon Resins market scenario on a global and regional level. The regional scope of the study covers key regions namely North America, Europe, ...
Aromaticity-antiaromaticity switch upon singlet-triplet transition of some biologically and synthetically important monoheterocycles (heteroatom = N, O, Si, P, and S) derived from benzene, naphthalene and anthracene was studied by employing energetic, magnetic and structural aromaticity criteria, at the density functional theory (DFT) level. The relationship between spin density distribution, (anti)aromaticity and singlet-triplet energy gaps, in the studied molecules, was found. In general, spin delocalization results in antiaromaticity, spin density localization to one ring in bi- and tricycles localizes antiaromaticity and spin localization on a heteroatom reduces global and local antiaromaticity. The latter reaches nonaromaticity in the case of silicon atoms which have larger orbitals and show more tendency to accept unpaired electrons. Spin density localization in bi- and tricycles allows benzene subunit(s) to develop local aromaticity, which, when combined with nonaromatic silacycle and ...
Quantum-Topology-Atoms-in-Molecules (QTAIM) distills the topology of ρ into key points called critical points. One of these having two negative eigenvalues of the density Hessian at that point (and hence a trace of -1) is labelled a bond critical point. In benzene, sensibly enough, it appears at the mid point of each C-C bond. At this point, it presumably reflects the σ contributions to the density far more than the π contributions. Indeed, its a node for the π system. So an aromaticity metric that uses a region of ρ that represents a node in the π distribution is indeed an interesting one! Of course, we now know that the six-fold symmetry of benzene is due to the σ framework, and not the π manifold. Is that what Shannon aromaticity measures? This leaves magnetic aromaticity, i.e the magnetic response we call a ring current, a quite different measure. Here again of course, the magnetic response of the σ and π electrons is quite different.. ...
GC Application #16187: Polynuclear Aromatic Hydrocarbons (PAHs): US and EU Analytes on ZB-MR1. Column used: Zebron™ ZB-MultiResidue™-1, GC Cap. Column 30 m x 0.25 mm x 0.25 µm, Ea Part#: 7HG-G016-11
Körner studied chemistry at Giessen, where he graduated in 1860. In 1866, he became assistant to Kekulé at Ghent. In 1867, when Kekulé was called to Bonn, Körner left Ghent for Palermo where entered the laboratory of Stanislao Cannizzaro, and occupied himself with the study of the aromatic compounds. Besides his work on aromatic compounds, his interest in botany led him to the study of many vegetable substances. In 1870, he accepted the chair of organic chemistry at Scuola Superiore di Agricoltura (School of Agriculture, University of Milan), where he retained until 1922, when for reasons of health he resigned his chair at the age of 83. ...
DDQ/H+ oxidation system which is known to oxidize a variety of aromatic donors with oxidation potential as high as 1.8 V vs. SCE to the corresponding cation radicals can be effectively employed for the preparation of a variety of polyaromatic hydrocarbons. The development of DDQ/H+ oxidation system for oxidative C-C bond formation (or Scholl reaction) also allowed us to provide insight into the controversial arenium-ion (proton transfer) versus cation-radical (electron transfer) pathways for the Scholl reaction. A series of carefully-designed experiments provided evidences in support of cation radical pathway for the Scholl reaction. A detailed case study of oxidative cyclodehydrogenation of tetraveratrylethylene was also undertaken using a variety of traditional !-electron oxidants (such as FeCi}, NO+BF4-, and DDQ/H+), in order to further probe the arenium ion versus cation radical pathways for the Scholl reaction. This case study further asserted that oxidative C-C bond formations most likely occur
Essential Oils Are Complex Mixtures of Aromatic CompoundsEssential oils are made of volatile aromatic compounds. Volatile aromatic compounds are small organic molecules that tend to change from the liquid state to the gas state at room temperature. You know, these molecules are so incredibly small that a single drop of
Advances in Polycarbonates includes such topics as theory and modelling, synthesis of new polycarbonates, characterization, development of enhanced properties in polycarbonates (such as conductivity, weatherability, higher heat or better low temperature ductility), recycling, and process chemistry. A variety of international researchers from industry, government, and academia have provided a diverse array of recent research.
Reactions of Aromatic Compounds: A Reaction Map. Lets map out all of the reactions weve learned in this section on aromatic rings + substituents. The list comes to about 25, including the six key electrophilic aromatic substitution reactions, the Wolff-Kishner and Clemmensen, reduction of nitro groups, the Baeyer-Villiger oxidation, sidechain oxidation, desulfonylation, and amine protection.. Also included is a few reactions we actually havent covered yet - such as diazonium salt formation and Sandmeyer reactions. These are often covered in the chapter on amines, but theyre going in here regardless.. File: (PNG). Alternatively: (PDF). ...
Among inactive halogenated aromatic compounds, in particular, chlorinated aromatic compounds have extremely low reactivity as compared to corresponding halogenated aromatic compounds of non-chlorinated series and no effective reaction agent or catalyst have been available . However, because the above described chlorinated compounds are industrially producible and available at a low price, recently, various kinds of reaction agents and catalysts have been developed to achieve the nucleophilic substitution reaction of inactive chlorinated aromatic compounds. For example, in L. I. Goryunov and V. D. Shteingarts, Russ. J. Org. Chem., 29, 1849-1855 (1993), it is disclosed that using Rh complex, which is expensive and difficult to be industrially produced, as a catalyst and chlorobenzene as a raw material, methoxybenzene can be obtained in the yield of 60 to 75% by reacting the chlorobenzene at reaction temperature between 80°C and 180°C for 4 days to 1 hour. In U.S. Pat. No. 5,315,043 or U.S. Pat. ...
Aromatic compounds are important contaminants that limit the intended uses of water resources. Both polar and non-polar substances, such as phenols, aromatic sulfonates, lignin-sulfonic acids, humic and fulvic substances (acids) and mono- and poly-aromatic hydrocarbons, their alkyl-substituted derivatives, respectively, are among the potential aromatic micropollutants. During the last 5 - 10 years, an analytical approach has been developed on the basis of total fluorescence measurement of the original water sample and its organic solvent (cyclohexane) extract. It has been demonstrated and verified that polar aromatic compounds fluoresce only in the original water sample, whereas non-polar (hydrophobic) compounds fluoresce in an organic solvent (e.g. cyclohexane) extract. During extraction, polar compounds remain in the water sample. This method has been used in a country-wide survey in drinking water aquifers, as well as in several environmental impact assessment studies, particularly for ...
The gram-negative metal-reducing microorganism, previously known as strain GS-15, was further characterized. This strict anaerobe oxidizes several short-chain fatty acids, alcohols, and monoaromatic compounds with Fe(III) as the sole electron acceptor. Furthermore, acetate is also oxidized with the reduction of Mn(IV), U(VI), and nitrate. In whole cell suspensions, the c-type cytochrome(s) of this organism was oxidized by physiological electron acceptors and also by gold, silver, mercury, and chromate. Menaquinone was recovered in concentrations comparable to those previously found in gram-negative sulfate reducers. Profiles of the phospholipid ester-linked fatty acids indicated that both the anaerobic desaturase and the branched pathways for fatty acid biosynthesis were operative. The organism contained three lipopolysaccharide hydroxy fatty acids which have not been previously reported in microorganisms, but have been observed in anaerobic freshwater sediments. The 16S rRNA sequence indicated ...
Thermoplastic compositions are described, containing a cycloaliphatic polyester resin, along with selected polycarbonates or copolycarbonates. The polycarbonates are usually based on dihydroxydiphenyl cyclohexanes, or on bisphenols prepared from cyclic monoterpene precursors. The compositions may be transparent or translucent. Moreover, they may include a rubbery impact modifier. Related processes and articles are also described.
However, there are many molecules where lone pair DO participate to aromaticity. Below are several examples. Take furan for example; oxygen has two lone pairs of electrons. One of them is in a geometry parallel to the pi-bond system. Therefore, these electrons DO participate in the pi-bond system and add 2 electrons the pi-bond count resulting in 4*1+2=6 electrons, therefore furan is aromatic. Imidiazole is molecule that has two nitrogen atoms; one nitrogen participating in pi-bonding and not contributing lone pairs, while the other is not participating in pi-bonding but contributes electrons the pi-bond count. The 4*1+2=6 electron count for imidazole renders it aromatic.. ...
Interestingly, over half of the plants listed above are in the mint family (Lamiaceae) except for marigolds (Asteraceae or composite family), lemongrass (Poaceae or grass family), garlic (Alliaceae or onion family) and petunias (Solanaceae or nightshade family). The Lamiaceae are frequently aromatic, which is why they are so popular for cooking, but aromatic compounds are often a plants defense against herbivory, which is why plants in the mint family are so good at repelling insects and other pests. Luckily for us humans, we find many of these plant odors attractive, so why not plant a few or all of these garden selections to enjoy a fragrant and relatively bug-free summer ...
Understanding of interactions among molecules is essential to elucidate the binding of pharmaceuticals on receptors, the mechanism of protein folding and self-assembling of organic molecules. While interactions between two aromatic molecules have been examined extensively, little is known about the interactions between two antiaromatic molecules. Theoretical investigations have predicted that antiaromatic molecules should be stabilized when they stack with each other by attractive intermolecular interactions. Here, we report the synthesis of a cyclophane, in which two antiaromatic porphyrin moieties adopt a stacked face-to-face geometry with a distance shorter than the sum of the van der Waals radii of the atoms involved. The aromaticity in this cyclophane has been examined experimentally and theoretically. This cyclophane exhibits three-dimensional spatial current channels between the two subunits, which corroborates the existence of attractive interactions between two antiaromatic π-systems. Little
TY - JOUR. T1 - Aromaticity in catalysis: metal ligand cooperation via ligand dearomatization and rearomatization. AU - Huang, Kuo-Wei. AU - Goncalves, Theo. AU - Dutta, Indranil. N1 - KAUST Repository Item: Exported on 2021-02-15 Acknowledgements: Financial support and the service of Ibex, Shaheen 2 High Performance Computing Facilities were provided by King Abdullah University of Science and Technology (KAUST).. PY - 2021/2/9. Y1 - 2021/2/9. N2 - Unlike the conventional model of transition metal catalysis, ligands in metal-ligand cooperative (or bifunctional) catalysis are involved in the substrate activations. Such processes have offered unique mechanistic understandings and led.... AB - Unlike the conventional model of transition metal catalysis, ligands in metal-ligand cooperative (or bifunctional) catalysis are involved in the substrate activations. Such processes have offered unique mechanistic understandings and led.... UR - UR - ...
The first comprehensive theoretical investigation of structural, energetic, and electronic changes in a sumanene skeleton, C21H12, upon a step-wise deprotonation process is performed. This study is complemented by a detailed consideration of aromaticity in target bowl-shaped systems, including neutral sumane
J. Am. Chem. Soc. 1996, 118, On the Question of Stability, Conjugation, and Aromaticity in Imidazol-2-ylidenes and Their Silicon Analogs Christoph Heinemann, Thomas Mu1ller, Yitzhak Apeloig,*,
Microorganisms are known to be capable of degrading diverse chemical substances including man-made chemicals in the environment that are mostly aromatic compounds. This diagram illustrates combination patterns of reaction modules for biodegradation of aromatic compounds, consisting of three main types of ring dihydroxylation modules, followed by meta- or ortho-cleavage modules, together with an optional preprocessing module for converting methyl group to carboxyl group on the aromatic ring ...
see article for more examples. Abstract. A mild, complete hydrogenation of aromatic rings catalyzed by heterogeneous 10% Rh/C proceeds at 80 C in water under 5 atm of H2 pressure and is applicable to the hydrogenation of various carbon and heteroaromatic compounds such as alkylbenzenes, biphenyls, pyridines and furans.. ...
Aromatic Compounds Market Report offered by Market Size Forecasters gives a market overview of the Aromatic Compounds industry which covers product scope, market revenue, opportunities, growth rate, sales volumes and figures, the report also explores the worldwide players of the market and is segmented by region, type and application with forecast to 2022.
I give tutorial classes in organic chemistry throughout the three years of the course. Much of the teaching is problem based in order to build up both mechanistic and synthetic expertise across a broad range of the subject. There is some [but not much] specialisation in the third year; if you choose some of the topics I know little about, you will be taught by experts in other colleges on an exchange arrangement. In the department I give second year lecture courses on saturated ring chemistry, and on oxidation and reduction in organic chemistry. I also organise and contribute to a second year supplementary subject on aromatic heterocyclic and pharmaceutical chemistry. ...
Biography. During my master project in Biomedical Chemistry at the TU/e I studied ring-chain equilibria in a host-guest system based on aromatic peptides and cucurbit[8]uril. After this I joined the Shih-group at the Wyss institute in Boston for an internship. In this internship the research was focused on DNA-origami, drug delivery and the activation of the human immune system. ...
1AQX: Structures of class pi glutathione S-transferase from human placenta in complex with substrate, transition-state analogue and inhibitor.
Dr King reports relationships with Aclaris Therapeutics, Concert Pharmaceuticals, Eli Lilly and Company, Pfizer, and Regeneron. Dr Guttman reports relationships with AbbVie, Almirall, Anacor Pharmaceuticals, Asana Biosciences, Celgene, Dermira, Eli Lilly and Company, Galderma Research & Development, Glenmark Generics, Janssen Pharmaceuticals, Kyowa Hakko Kirin Pharma, Leo Pharma, Medimmune, Mitsibushi Pharma, Novartis, Pfizer, Regeneron, sanofi-aventis, Sanofi/Regeneron, Stiefel, and Vitae Pharmaceuticals. Dr Meisenheimer has disclosed no relevant financial relationships. ...
항암제로 약효가 뛰어난 Streptonigrin은 독성이 강한 단점이 있어서 많은 학자들이 새로운 항암제의 개발을 시도하고있다. 최근 보고된 Johnson연구진의 보고에 의하면 Streptonigrin의 모핵인 Quinoline-5,5-dione유도체가 강한 항암효과를 가지고 있는것으로 알려졌다. 본 실험에서는 분자내 고리화 반응을 통해 Quinoline-5,8-dione을 모핵으로 한 Pyridino[2,3, f]-indole-4,9-dione유도체와 기타 heteroaromatic compound를 합성하였다. 즉, 6,7-Dichloro-quinoline-5,8-dione을 NH_(4)0H 존재하에서 α-cyanoethylester와 반응시켜 6-( α -cyano- α -ethoxycarbonyl -methyl )-7-chloro-quinoline-5,8-dione(compoundⅠ )을 합성하였다. 이를 지방족아민과 반응시켜서 2-amino-3-ethoxycarbonyl-N-alkyl-pyridino[2, 3, f] indole-4,9-dione 유도체(compoundⅡa-e)를 얻었으나 방향족아민과의 반응에서는 분자내 고리화 반응이 일어나지않고 친핵성 치환 반응만이 ...
Name: Chemistry of hydrocarbon compounds > Aromatic compound synthesis > From alicyclic > Polycyclic product or with olefinic unsaturation in ...
This video lecture, part of the series Chemistry 3B: Chemical Structure and Reactivity (2010) by Prof. Peter C. Vollhardt, does not currently have a detailed description and video lecture title. If you have watched this lecture and know what it is about, particularly what Chemistry topics are discussed, please help us by commenting on this video with your suggested description and title. Many thanks from ...
The blog mainly contains Study guides for various topics in JEE Syllabus and Revision material of Chemistry. Model questions and Practice Questions are provided in separate blogs.. ...
It has been demonstrated previously that some adducts formed between endogenously activated polyaromatic hydrocarbons and DNA lead to significant stabilization of the DNA secondary structure (Lukin et al., 2011; Zaliznyak et al., 2006). Systematic study o
Rings are calculated using MIB by We calculate Bemis-Murcko Scaffolds (argument: -scaffold). For each BM Scaffold, we enumerate ring systems (argument: -ringSystems). For each ring system, we enumerate simple rings (argument: -simpleRings). We have to fudge a bit on simple rings that break aromaticity, tautomers and so on. We hope that this ring-based view of purchasable chemical space will be useful notwithstanding a few problems. Like all of ZINC, you must agree to use it at your own risk. NB as of March 13, 2012, only about 10% of the molecules in ZINC have been processed for rings. We expect to have 95% coverage by April 1, 2012. ...
The invention relates to the use of N-isobutylamide 2E, 4E-decadien acid (trans-pellitorin) in the form of an aromatic substance, in particular a saliva stimulating aromatic substance preferably for food, buccal hygiene or gustatory preparations. The preparations, semifinished products, compounds of odorant, aromatic and gustatory substances which contain trans-pellitorin and a method for the production of said trans-pellitorin are also disclosed.
View Notes - Chapter 16 September 19 from CHEM 234-54 at UGA. however: 3 2.) Reduction of Aryl Alkyl Ketones : Example: A neighboring (adjacent) aromatic ring activates carbonyl groups for reduction
Returns the number of aromatic rings in the molecule. This number is calculated from the smallest set of smallest aromatic rings (SSSAR), which might contain rings that are not part of the standard SSSR ring set. As a consequence, the sum of the aliphatic ring count and the aromatic ring count can sometimes be greater than the ring count value. The difference is the sign of a macroaromatic ring system. ...
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SPE Supra-Clean NH2-S (Amino) Column, 100 mg/1 mL is recommended for extracting polar to mid-polar aromatic compounds when analyzing basic compounds, polar amine compounds, and carbohydrates.
SPE Supra-Clean Phenyl (PH-S) 96 Well Plate, 100 mg/2 mL. Recommended for extracting non-polar to mid-polar aromatic compounds when analyzing Benzodiazepines in biological matrices.
Natures Own all natural terpenes are an effects-rich terpenes base combined with a variety of other aromatic compounds.The Natures Own proprietary blend of our all natural terpenes mix.
AROMATICS, also known as arenes, is any of a large class of unsaturated chemical compounds characterized by one or more planar rings of atoms joined by covalent bonds of two different kinds ...
GenDR A curated database of genes associated with dietary restriction in model organisms either from genetic manipulation experiments or gene expression profiling.. ...
Aromatic hydrocarbons[edit]. Aromatic hydrocarbons show distinct molecular ion peak.benzylic cleavage is pretty common. When ... Aromatic ethers can generate the C6H5O+ ion by loss of the alkyl group rather than H; this can expel CO as in the phenolic ... For aromatic carbonyl compounds, Alpha-cleavages are favorable primarily to lose G· (M - 1,15, 29…) to form the C6H5CO+ ion (m/ ... Aromatic amines have intense molecular ion peaks. For anilines, they prefer to lose a hydrogen atom before the expulsion of HCN ...
Main article: Polycyclic aromatic hydrocarbon. Polycyclic aromatic hydrocarbons (PAHs) are aromatic hydrocarbons that consist ... An aromatic hydrocarbon or arene[1] (or sometimes aryl hydrocarbon)[2] is a hydrocarbon with sigma bonds and delocalized pi ... Other monocyclic aromatic hydrocarbon[edit]. Other monocyclic aromatic hydrocarbon include Cyclotetradecaheptaene or ... Fetzer, J. C. (2000). "The Chemistry and Analysis of the Large Polycyclic Aromatic Hydrocarbons". Polycyclic Aromatic Compounds ...
Cook, J. W. (1931). "CCCL.-Polycyclic aromatic hydrocarbons. Part VI. 3 : 4-Benzphenanthrene and its quinone". J. Chem. Soc.: ... Olympicene has 18 pi electrons in its ring system; as it is a flat molecule, this makes it an aromatic molecule. The central ... The structure of overcrowded aromatic compounds. Part VI. The crystal structure of benzo[c]phenanthrene and of 1,12- ... ring is not an aromatic ring. A very similar molecule (benzo[c]phenanthrene) which lacks the -CH2- spacer between the two sides ...
polycyclic aromatic hydrocarbons. The ferromagnesian minerals are isolated and show no signs of alteration. As concerns the ...
Non-aromatic hydrocarbons. As of 2009 these had become the most commonly used drilling fluids; eliminating the aromatics ... Fluids used include water, ethanol/water and water/ethylene glycol mixtures, petroleum fuels, non-aromatic hydrocarbons, and n- ... They are inexpensive and easily available, and were once in common use; disadvantages include flammability and the aromatics ...
"Electron transfer from aromatic hydrocarbons and their pi-complexes with metals. Comparison of the standard oxidation ... With a simple proton NMR spectrum comprising two signals due to the 2 aromatic hydrogens (2H) and four methyl groups (12H), ... Röhrscheid, F. (2012). "Carboxylic Acids, Aromatic". Ullmann's Encyclopedia of Industrial Chemistry. doi:10.1002/14356007.a05_ ... Hydrocarbons obtained by the action of methyl chloride on benzene in the presence of aluminum chloride]. Chem. Ber. 12: 329-332 ...
"Chlorinated Benzenes and other Nucleus-Chlorinated Aromatic Hydrocarbons" Ullmann's Encyclopedia of Industrial Chemistry, 2012 ... Chlorobenzene is an aromatic organic compound with the chemical formula C6H5Cl. This colorless, flammable liquid is a common ... Gerald Booth (2007). "Nitro Compounds, Aromatic". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi: ... "Chlorinated Hydrocarbons". Ullmann's Encyclopedia of Industrial Chemistry. doi:10.1002/14356007.a06_233.pub2. ISBN 3527306730. ...
Polycyclic aromatic hydrocarbons • Radioactive contamination • Volatile organic compounds Waste - Electronic waste • Great ... Hydrocarbons • Perchlorate • Pesticides • Persistent organic pollutant • PBBs • PBDEs • Toxic heavy metals • PCB • Dioxin • ...
Friedel-Crafts test for aromatic hydrocarbons[edit]. Reaction of chloroform with aromatic compounds using an aluminium chloride ... 25.10 Aromatic Hydrocarbons and Aryl Halides - Classification test. ISBN 978-1-4390-4914-3 ... Friedel-Crafts alkylation involves the alkylation of an aromatic ring with an alkyl halide using a strong Lewis acid, such as ... Price, C. C. (1946). "The Alkylation of Aromatic Compounds by the Friedel-Crafts Method". Org. React. 3: 1. doi:10.1002/ ...
"Aromatic Hydrocarbons as Ligands. Recent Advances in the Synthesis, the Reactivity and the Applications of Bis(η6-arene) ... and polycyclic aromatic compounds (e.g. naphthalene). Also known as reductive Friedel-Crafts reaction, the Fischer-Hafner ...
... hydrocarbons • and polycyclic aromatic hydrocarbons • other acute and chronic toxicants In many cases, huge ponds sit with very ... silt and clay mixed with leftover hydrocarbons and other toxic substances. Tailings are being created at a rate of 2,000 or so ...
... aliphatic and aromatic hydrocarbons; sulfonic and phosphonic acids; amino, hydroxycarboxylic, and carboxylic acids; purines and ... has revealed that the interstellar medium contains a suite of complex gas-phase carbon compounds called aromatic hydrocarbons, ...
"Microbes biodegrade aromatic hydrocarbons". Biosphere Plastic. Retrieved 20 May 2011. "Oxo-degradable plastics: do they ...
Cite journal requires ,journal= (help); Missing or empty ,title= (help) Pampaloni, G. (2010). "Aromatic hydrocarbons as ligands ...
Polycyclic aromatic hydrocarbons (PAHs), aldehydes, volatile organic compounds (VOCs), phenolic compounds, flavors, tobacco ... polycyclic aromatic hydrocarbons; GS-MS, gas chromatography - mass spectrometry; ICP-MS, inductively coupled plasma - mass ...
Pampaloni, Guido (2010). "Aromatic hydrocarbons as ligands. Recent advances in the synthesis, the reactivity and the ... The molecule is aromatic and avoids exceeding the octet on carbon by having only a total of six electrons in the five bonds ... It is an aromatic compound, with six π electrons (satisfying Hückel's rule) delocalised over a cyclic planar system; each of ... It forms orange-yellow 1:1 adduct witth picryl chloride, probably due to π-stacking of the aromatic systems. Oxidation with ...
Most aromatic hydrocarbons are benzenoid. Notable counterexamples are cyclooctadecanonaene, azulene and trans-bicalicene. ...
Polycyclic aromatic hydrocarbons, long carbon-chain molecules such as polyynes, and fullerenes are all potentially important. ... The origin of most DIBs remains unknown, with common suggestions being polycyclic aromatic hydrocarbons and other large carbon- ... Kroto, H. W. (1987). Leger, Alain (ed.). Chains and Grains in Interstellar Space (PDF). Polycyclic Aromatic Hydrocarbons and ... "Ultrafast Studies on the Photophysics of Matrix-Isolated Radical Cations of Polycyclic Aromatic Hydrocarbons". The Journal of ...
Cerniglia, Carl E. (1992). "Biodegradation of polycyclic aromatic hydrocarbons". Biodegradation. 3 (2-3): 351-368. doi:10.1007/ ... Typical stoichiometries for the hydroxylation of a generic hydrocarbon are these: 2 R3C-H + O2 → 2 R3C-OH R3C-H + O2 + 2e- + 2 ...
Many studies have been conducted using polycyclic aromatic hydrocarbons (PAH), which are low molecular hydrocarbons found in ... When an aromatic hydrocarbon was introduced to the molecular oxygen in experimental conditions, a dihydrodiol intermediate was ... The creosote (often called "creosote oil") consists almost wholly of aromatic hydrocarbons, with some amount of bases and acids ... Elder, JF; Dresler, PV (1988). "Accumulation and bioconcentration of polycyclic aromatic hydrocarbons in a nearshore estuarine ...
"Biodegradation of polycyclic aromatic hydrocarbons". Biodegradation. 3 (2-3): 351-368. doi:10.1007/BF00129093. Aryl hydrocarbon ... Many species are also capable of oxidizing polycyclic aromatic hydrocarbons, a class of stable organic molecules that tends to ...
Under these conditions, aliphatic hydrocarbons form rings and lose hydrogen to become aromatic hydrocarbons. The aromatic ... The extraction step of aromatics from the reformate is designed to produce aromatics with lowest non-aromatic components. ... Due to the cyclic continuous pi bonds between the carbon atoms, benzene is classed as an aromatic hydrocarbon. It is sometimes ... Most people in developed countries have measureable baseline levels of benzene and other aromatic petroleum hydrocarbons in ...
Benzo[c]fluorene is a polycyclic aromatic hydrocarbon (PAH) with mutagenic activity. It is a component of coal tar, cigarette ... Seto H, Ohkubo T, Kanoh T, Koike M, Nakamura K, Kawahara Y (1993). "Determination of polycyclic aromatic hydrocarbons in the ... Benzo[c]fluorene belongs to a group of compounds called polycyclic aromatic hydrocarbons (PAHs). PAHs and their derivatives are ... Development of a Relative Potency Factor (RPF) Approach for Polycyclic Aromatic Hydrocarbon (PAH) Mixtures (External Review ...
Harvey, G. R. (1991). Polycyclic Aromatic Hydrocarbons: Chemistry and Carcinogenicity. Cambridge, UK: Cambridge University ...
"Thermal Reactivity of Polynuclear Aromatic Hydrocarbons". The Journal of Organic Chemistry. 28 (8): 2050-2057. doi:10.1021/ ... Inaba, S (1982). "Metallic nickel as a reagent for the coupling of aromatic and benzylic halides". Tetrahedron Letters. 23 (41 ...
... (also known as superbenzene) is a polycyclic aromatic hydrocarbon (PAH) comprising seven peri-fused benzene rings. Its ... Fetzer, J. C. (2000). The Chemistry and Analysis of the Large Polycyclic Aromatic Hydrocarbons. New York: Wiley. Karpatite. ... Mackay, D.; Shiu, W. Y. (1977). "Aqueous solubility of polynuclear aromatic hydrocarbons". Journal of Chemical & Engineering ... In the Clar sextet case, the most stable structure for coronene has only the three isolated outer sextets as fully aromatic ...
In February 2014, NASA announced a greatly upgraded database for tracking polycyclic aromatic hydrocarbons (PAHs), including ... They belong to the chemical class of polycyclic aromatic hydrocarbons. Related compounds include cyclopentapyrenes, ... "Polycyclic aromatic hydrocarbons in grilled food". J Agric Food Chem. 31 (4): 867-873. doi:10.1021/jf00118a049. PMID 6352775. ... Benzopyrene is a component of pitch and occurs together with other related pentacyclic aromatic species such as picene, ...
Aromatic hydrocarbons contain conjugated double bonds. This means that every carbon atom in the ring is sp2 hybridized, ... alkynes (acetylenes): aliphatic hydrocarbons which have one or more triple bonds. The rest of the group is classed according to ... The aliphatic hydrocarbons are subdivided into three groups of homologous series according to their state of saturation: ... The purine nucleoside bases are notable polycyclic aromatic heterocycles. Rings can also fuse on a "corner" such that one atom ...
Aromatics in hydrocarbons. Essential oil in alcohol-based essences. The bottle and the test were developed in 1890 by Stephen M ... "Determination of Aromatics and Napthenes in Complex Hydrocarbon Mixtures Containing Olefins". Analytical Chemistry, volume 19, ... Unsaturated hydrocarbons in gasoline. Mineral oil adulteration in turpentine. Mercaptans in naphtha. Ortho-xylene in recycled ... Nitrogen Tetroxide Method as Applied to Petroleum Hydrocarbons In the Gasoline Boiling Range". Industrial & Engineering ...
Gibson DT, Koch JR, Kallio RE (1968). "Oxidative degradation of aromatic hydrocarbons by microorganisms. I Enzymatic formation ...
Main article: Polycyclic aromatic hydrocarbon. Polycyclic aromatic hydrocarbons (PAHs) are aromatic hydrocarbons that consist ... An aromatic hydrocarbon or arene[1] (or sometimes aryl hydrocarbon)[2] is a hydrocarbon with sigma bonds and delocalized pi ... Other monocyclic aromatic hydrocarbon[edit]. Other monocyclic aromatic hydrocarbon include Cyclotetradecaheptaene or ... Fetzer, J. C. (2000). "The Chemistry and Analysis of the Large Polycyclic Aromatic Hydrocarbons". Polycyclic Aromatic Compounds ...
Hydroxylated polycyclic aromatic hydrocarbons as biomarkers of exposure to wood smoke in wildland firefighters. Adetona O, ... Urinary polycyclic aromatic hydrocarbon (OH-PAH) metabolite concentrations and the effect of GST polymorphisms among US Air ... Biomonitoring of polycyclic aromatic hydrocarbons exposure in small groups of residents in Brisbane, Australia and Hanoi, ... Urinary polycyclic aromatic hydrocarbon metabolites as biomarkers to woodsmoke exposure - results from a controlled exposure ...
Wikimedia Commons has media related to Polycyclic aromatic hydrocarbons.. *ATSDR - Toxicity of Polycyclic Aromatic Hydrocarbons ... National Pollutant Inventory: Polycyclic Aromatic Hydrocarbon Fact Sheet. *Understanding Polycyclic Aromatic Hydrocarbons NASA ... A polycyclic aromatic hydrocarbon (PAH) is a hydrocarbon-a chemical compound containing only carbon and hydrogen-that is ... The terms polyaromatic hydrocarbon[1] or polynuclear aromatic hydrocarbon[2] are also used for this concept.[3] ...
Exposure to polycyclic aromatic hydrocarbons usually occurs by breathing air contaminated by wild fires or coal tar, or by ... How can polycyclic aromatic hydrocarbons (PAHs) affect my health?. *How likely are polycyclic aromatic hydrocarbons (PAHs) to ... What are polycyclic aromatic hydrocarbons (PAHs)?. *What happens to polycyclic aromatic hydrocarbons (PAHs) when they enter the ... What are polycyclic aromatic hydrocarbons (PAHs)?. Polycyclic aromatic hydrocarbons (PAHs) are a group of over 100 different ...
Polycyclic aromatic hydrocarbon, polycyclic aromatic hydrocarbon (en); هيدرو كربون أروماتي متعدد الحلقات, هيدروكربون أروماتي ... polycyclic aromatic compound,. aromatic hydrocarbon,. pollutant,. non-methane volatile organic compound. Part of. response to ... Media in category "Polycyclic aromatic hydrocarbons". The following 123 files are in this category, out of 123 total. ... hydrocarbons composed of multiple aromatic rings (en); węglowodór aromatyczny, w którym występują przynajmniej dwa ...
Toxicological Profile for Polycyclic Aromatic Hydrocarbons (PAHs). Toxicological Profile Information. The ATSDR toxicological ... Toxicological profile for Polycyclic Aromatic Hydrocarbons (PAHs). Atlanta, GA: U.S. Department of Health and Human Services, ...
ToxFAQs for Polycyclic Aromatic Hydrocarbons (PAHs). Environmental Protection Agency. *Consumer Factsheet on: BENZO(A)PYRENE ... Polycyclic aromatic hydrocarbons (PAHs) are a class of chemicals that occur naturally in coal, crude oil, and gasoline. They ...
Purchase Metabolic Activation of Polynuclear Aromatic Hydrocarbons - 1st Edition. Print Book & E-Book. ISBN 9780080238357, ... Metabolic Activation of Polynuclear Aromatic Hydrocarbons deals with the metabolic activation of polynuclear aromatic ... Metabolic Activation of Polynuclear Aromatic Hydrocarbons 1st Edition. 0.0 star rating Write a review ... Research on polycyclic aromatic hydrocarbons pertaining to the Bay-region theory is also presented. ...
... for research into environmental contaminants in food and feed such as polycyclic aromatic hydrocarbons (PAHs). ... Polycyclic aromatic hydrocarbons. Wageningen Food Safety Research is National Reference Laboratory (NRL) for research into ... The EU-RL for polycyclic aromatic hydrocarbons in Feed and Food as laid down in Regulation (EU) 2017/625 contributes to the ... Wageningen Food Safety Research is National Reference Laboratory for polycyclic aromatic hydrocarbons (PAHs) and is involved in ...
Polycyclic aromatic compounds (PAH) are a very large number of naturally occurring and man-made chemicals. The pure compounds ... Polycyclic aromatic hydrocarbons (PAH) This website has limited functionality with javascript off. Please make sure javascript ... or scan the QR code. ... Polycyclic aromatic compounds (PAH) are a very large number of naturally occurring and man-made chemicals. The pure compounds ...
... Jejal Reddy Bathi,1,2 Robert E. Pitt,1 and Shirley E. Clark3 ... J. R. Bathi, Associations of polycyclic aromatic hydrocarbons (PAHs) with urban creek sediments, Ph.D. thesis, Department of ... C. J. Diblasi, H. Li, A. P. Davis, and U. Ghosh, "Removal and fate of polycyclic aromatic hydrocarbon pollutants in an urban ... Polycyclic aromatic hydrocarbons (PAHs) are a class of frequently detected organic pollutants in urban stormwater runoff. ...
T. Abdulazeez, "Polycyclic aromatic hydrocarbons," A Review. Lawal, Cogent Environmental Science, vol. 3, Article ID 1339841, ... L. Donta, Polycyclic Aromatic Hydrocarbons (PAH) Factsheet, European Union JRC 66955, Joint Research Center, Institute for ... Polycyclic aromatic hydrocarbons (PAHs) comprise a large group of organic compounds containing two or more fused benzene rings ... V. K. Singh, D. K. Patel, R. Jyoti, S. Ram, N. Mathur, and M. K. J. Siddiqui, "Blood levels of polycyclic aromatic hydrocarbons ...
Toxicity of Polycyclic Aromatic Hydrocarbons (PAHs) Who Is at Risk of Exposure to Polycyclic Aromatic Hydrocarbons (PAHs)? ... A. Polynuclear aromatics (PNAs). There may be B. Polynuclear hydrocarbons. more than one C. Polynuclear aromatic hydrocarbons. ... Toxicity of Polycyclic Aromatic Hydrocarbons (PAHs) Where Are Polycyclic Aromatic Hydrocarbons (PAHs) Found? Learning Upon ... Toxicity of Polycyclic Aromatic Hydrocarbons (PAHs) What Are the Routes of Exposure for Polycyclic Aromatic Hydrocarbons (PAHs ...
FSANZ Internet Our science Monitoring the safety of the food supply Survey of Polycyclic aromatic hydrocarbons ( PAH) ... Polycyclic aromatic hydrocarbons (PAH) are naturally occurring compounds found in the environment. They result from natural ... The full report of Polycyclic aromatic hydrocarbons in foods available in Australia is available on the FSANZ website HERE ...
... Cefas action levels do not contain values for individual PAHs. The action levels are ... 17/02/2018 ...
Filed under: polycyclic aromatic hydrocarbons, pops, air pollution indicators, air emissions, pah, persistent organic ... Filed under: polycyclic aromatic hydrocarbons pops air pollution indicators air emissions pah persistent organic pollutants ... Change in polycyclic aromatic hydrocarbons emissions This website has limited functionality with javascript off. Please make ... or scan the QR code. ...
... both the polycyclic aromatic hydrocarbons (PAHs) and metals like arsenic that are associated with drilling accidents. By some ...
... 2018-01-1812. ... Citation: Fanick, E. and Kroll, S., "Polycyclic Aromatic Hydrocarbons in Diesel Engine Exhaust Both with and without ... One group of compounds typically found in exhaust, polycyclic aromatic hydrocarbons (PAH), usually occurs at very low ... Selective catalytic reduction Diesel particulate filters Diesel / compression ignition engines Hydrocarbons Combustion and ...
1-Pentene and 1-hexene transformation into aromatic hydrocarbons over H-ZSM-5, H-ZBS-11 and H-ZSM-11 modified with Zn(II), Ga( ... 1-Pentene and 1-hexene transformation into aromatic hydrocarbons over H-ZSM-5, H-ZBS-11 and H-ZSM-11 modified with Zn(II), Ga( ... Physical Chemistry Zeolite Catalysis Hydrocarbon High Activity These keywords were added by machine and not by the authors. ...
Keywords: ANAEROBIC; DIGESTION; MODEL; POLYNUCLEAR AROMATIC HYDROCARBONS; SLUDGE TREATMENT; TOXICS Document Type: Research ... Fate of polynuclear aromatic hydrocarbons during anaerobic digestion of municipal wastewater sludges ... The fate of six polynuclear aromatic hydrocarbons during anaerobic digestion of municipal sludges was investigated in a two- ...
KudoZ) Portuguese to English translation of hidrocarbonetos aromáticos e alifáticos: aliphatic and aromatic hydrocarbons [ ... aliphatic and aromatic hydrocarbons. Explanation:. Example:. A most probable number (MPN) procedure was developed to separately ... aliphatic and aromatic hydrocarbons. Explanation:. Example:. A most probable number (MPN) procedure was developed to separately ... enumerate aliphatic and aromatic hydrocarbon degrading bacteria, because most of the currently available methods are unable to ...
Aromatic hydrocarbons, C8. Regulatory process names 3 Translated names 44 IUPAC names 1 Other identifiers 2 ...
Use of this information is subject to copyright laws and may require the permission of the owner of the information, as described in the ECHA Legal Notice.. ...
Hydrocarbons, C10 aromaticsHydrocarbons, C10 aromatics. ... Hydrocarbons, C11 aromaticsHydrocarbons, C11 aromatics. ... Hydrocarbons, C9 aromaticsHydrocarbons, C9 aromatics. ... Hydrocarbons, C10, aromatics, EC Number:. 918-811-1. CAS Number:. 1189173-42-9 Molecular formula:. None available - not a ...
Thermal rearrangements of aromatic hydrocarbons have been shown to be important in areas of chemical research and industry ... Thermal rearrangements of aromatic hydrocarbons are considered to be unimolecular reactions that directly involve the atoms of ... Thermal rearrangements of aromatic hydrocarbons are generally carried out through flash vacuum pyrolysis (FVP). In a typical ... Many of the polycyclic aromatic hydrocarbons known to be tumorigenic or mutagenic are found in atmospheric aerosols, which is ...
... preferably vinyl substituted aromatic hydrocarbons, still more preferably vinyl monocyclic aromatic hydrocarbons. The most ... Vinyl aromatic polymer blocks are preferably made from one or more monovinyl aromatic hydrocarbons of the benzene series such ... The inert hydrocarbon solvent is preferably an alpha olefin or lower allcane although aromatic hydrocarbons such as benzene, ... polymer in its final usable form is completely soluble in certain hydrocarbon solvents, preferably aromatic hydrocarbons such ...
X-radiation and aromatic hydrocarbons, only aromatic hydrocarbons have not been previously implicated in human mammary ... Aromatic hydrocarbons are important environmental chemicals produced by the incomplete combustion of hydrocarbons for use in ... The role of aromatic hydrocarbons in the genesis of breast cancer Med Hypotheses. 1992 Jul;38(3):177-84. doi: 10.1016/0306-9877 ... Human exposure to aromatic hydrocarbon metabolites induces and promotes altered DNA by mechanisms described as increased ...
Polycyclic aromatic hydrocarbon (PAH) ecotoxicology in marine ecosystems.. Hylland K1.. Author information. 1. Norwegian ... Low levels of oil and hence polycyclic aromatic hydrocarbons (PAHs) are naturally present in the marine environment, although ...
Polycyclic Aromatic Hydrocarbons (PAHs). PAHs are Everywhere. PAHs are extremely common in the environment. Urban environments ... PAHs, short for polycyclic aromatic hydrocarbons, are a group of chemicals consisting of numerous carbon atoms joined together ...
Find Polycyclic Aromatic Hydrocarbon (PAH) Monitoring - Monitoring and Testing information on the worlds largest Environmental ... Polycyclic Aromatic Hydrocarbon (PAH) Monitoring. Articles & Whitepapers. * TESTEX AG, Zürich, Switzerland - Case Study "The ... Bordeaux (13-17 September 2015) CHROMATOTEC® was Gold Sponsor of 2015 International Symposium on Polycyclic Aromatic Compounds ...
  • PAHs are uncharged, non-polar molecules, with distinctive properties due in part to the delocalized electrons in their aromatic rings. (
  • This fact sheet answers the most frequently asked health questions about polycyclic aromatic hydrocarbons (PAHs). (
  • Polycyclic aromatic hydrocarbons (PAHs) are a group of over 100 different chemicals that are formed during the incomplete burning of coal, oil and gas, garbage, or other organic substances like tobacco or charbroiled meat. (
  • What happens to polycyclic aromatic hydrocarbons (PAHs) when they enter the environment? (
  • How might I be exposed to polycyclic aromatic hydrocarbons (PAHs)? (
  • How can polycyclic aromatic hydrocarbons (PAHs) affect my health? (
  • How likely are polycyclic aromatic hydrocarbons (PAHs) to cause cancer? (
  • Is there a medical test to show whether I've been exposed to polycyclic aromatic hydrocarbons (PAHs)? (
  • Polycyclic aromatic hydrocarbons (PAHs) are a class of chemicals that occur naturally in coal, crude oil, and gasoline. (
  • RIKILT is National Reference Laboratory (NRL) for research into environmental contaminants in food and feed such as polycyclic aromatic hydrocarbons (PAHs). (
  • RIKILT is National Reference Laboratory for polycyclic aromatic hydrocarbons (PAHs) and is involved in the analysis of PAHs in food and feed. (
  • Polycyclic aromatic hydrocarbons (PAHs) are persistent organic pollutants of high environmental concern with known carcinogenic activity. (
  • Polycyclic aromatic hydrocarbons (PAHs) are a class of frequently detected organic pollutants in urban stormwater runoff. (
  • Studies have identified particulate associated PAHs as the most abundant [ 7 - 10 ], which is expected based on their hydrophobic nature and low vapor pressure, especially for PAHs with more than three aromatic rings. (
  • This article offers a review on the application of nanoparticles (NPs) that have been used as sorbents in the analysis of polycyclic aromatic hydrocarbons (PAHs). (
  • Polycyclic aromatic hydrocarbons (PAHs) comprise a large group of organic compounds containing two or more fused benzene rings connected in linear, angular, or cluster arrangements. (
  • Chlorinated polycyclic aromatic hydrocarbons (Cl-PAHs) are a group of compounds comprising polycyclic aromatic hydrocarbons with two or more aromatic rings and one or more chlorine atoms attached to the ring system. (
  • Once the more easily processed materials and their breakdown products have completed their complicated journeys through the Gulf ecosystems, that still leaves the toxins that don't break down easily, both the polycyclic aromatic hydrocarbons (PAHs) and metals like arsenic that are associated with drilling accidents. (
  • Low levels of oil and hence polycyclic aromatic hydrocarbons (PAHs) are naturally present in the marine environment, although levels have increased significantly following human extraction and use of oil and gas. (
  • PAHs, short for polycyclic aromatic hydrocarbons, are a group of chemicals consisting of numerous carbon atoms joined together to form multiple rings. (
  • The particulate air pollutants contained mutagenic and carcinogenic polycyclic aromatic hydrocarbons (PAHs). (
  • Soot from the fires contained numerous carcinogens, notably polycyclic aromatic hydrocarbons (PAHs) that are ubiquitous products of incomplete combustion. (
  • The intertidal zone-a transitional boundary between terrestrial and marine environments-has important ecological functions, and receives polycyclic aromatic hydrocarbons (PAHs) from human activities, but how and to what extent anthropogenic factors influence the distribution of PAHs in this important niche remain largely unknown. (
  • Balcioglu, E. B. Potential effects of polycyclic aromatic hydrocarbons (PAHs) in marine foods on human health: a critical review. (
  • Polycyclic aromatic hydrocarbons (PAHs) are among the most prominent toxic compounds in the air. (
  • Polycyclic aromatic hydrocarbons (PAHs), including benzo[a]pyrene (BaP), are among the most prominent toxic air pollutants, posing a threat to human health because their metabolites and oxidation products are carcinogenic and mutagenic ( 1 ). (
  • Biodegradation of selected UV-irradiated and non-irradiated polycyclic aromatic hydrocarbons (PAHs). (
  • The primary interest was on 16 polycyclic aromatic hydrocarbons (PAHs) listed as priority pollutants by European Union (EU) and the United States Environmental Protection Agency (USEPA). (
  • Many members of the sphingomonad genus isolated from different geological areas can degrade a wide variety of polycyclic aromatic hydrocarbons (PAHs) and related compounds. (
  • In this paper we show that oxygenated polycyclic aromatic hydrocarbons (oxy-PAHs) are important cocontaminants that should be taken into account during risk assessment and remediation of sites with high levels of PAHs. (
  • Furthermore, we show that oxy-PAHs are toxic to both humans and the environment, although the toxicity seems to be manifested through other effects than those known to be important for polycyclic aromatic compounds in general, that is, mutagenicity and carcinogenicity. (
  • Herein we provide molecular evidence for a pathway involved in the elimination of the female germline due to prepregnancy and/or lactational exposure to polycyclic aromatic hydrocarbons (PAHs), environmental toxicants found in cigarette smoke. (
  • At least some aromatic hydrocarbons, including at least some PAHs exhibit fluorescence , which can be used to detect them. (
  • Gabet, S. (2004) Mobilisation of Polycyclic Aromatic Hydrocarbons (PAHs) in contaminated soils with biological surfactants. (
  • The researchers discovered polycyclic aromatic hydrocarbons (PAHs) with aliphatic side chains, which have been hypothesized to serve as "seeds" for soot particles in engine emissions . (
  • The team found direct evidence that aliphatically-bridged polycyclic aromatic hydrocarbons and PAHs with alkyl chains exist in the sampled gases of the soot-forming flame. (
  • Sorption is a key factor in determining the fate of polycyclic aromatic hydrocarbons (PAHs) in the environment. (
  • Atmospheric polycyclic aromatic hydrocarbons (PAHs) in Asia: a review from 1999 to 2004. (
  • Polycyclic aromatic hydrocarbons (PAHs) are present in both gaseous and particulate phases. (
  • Polynuclear aromatic hydrocarbons (PAHs) are a hazardous class of compounds that are found when drilling and burning fossil fuels. (
  • The Canadian Environmental Protection Act (CEPA) proclaimed in 1988 requires the Canadian Ministers of the Environment and of National Health and Welfare to assess the toxicity of different substances, including Polycyclic Aromatic Hydrocarbons (PAHs). (
  • Polycyclic aromatic hydrocarbons (PAHs) are a ubiquitous contaminant in urban environments. (
  • This study includes research into using UV light to remove Polycyclic Aromatic Hydrocarbons (PAHs) from municipal sludge. (
  • In this study, 16 polycyclic aromatic hydrocarbons (PAHs) were detected in sewage sludge samples from four wastewater treatment plants (WWTPs) in Qingdao, China. (
  • Analysis for sixteen types of Polycyclic Aromatic hydrocarbons (PAHs) from samples of raw and treated wastewater, sediments, sludge and plants growing along treated wastewater way was performed in October 1997. (
  • The results of investigations on the efficiency of the removal of polycyclic aromatic hydrocarbons (PAHs) from wastewater exposed to UV radiation are presented. (
  • In previous studies, the origin of the higher stability of kinked polycyclic aromatic hydrocarbons (PAHs) was found to be better π-bonding interactions, i.e., larger aromaticity, in kinked as compared to linear PAHs. (
  • Unregulated electronic-waste recycling results in serious environmental pollution of polycyclic aromatic hydrocarbons (PAHs) in Guiyu, China. (
  • Researcher using a combined gas chromatograph and mass selective detector (GC/MSD) to carry out analysis of polycyclic aromatic hydrocarbons (PAHs) in samples of UK air. (
  • The objective of this research project is to focus on the central hypothesis of the Southern California Particle Center and Supersite, which is that organic constituents associated with particulate matter-including quinones, other organic compounds (polycyclic aromatic hydrocarbons [PAHs], nitro-PAHs, and aldehydes/ketones), and metals-are capable of generating reactive oxygen species and acting as electrophilic agents. (
  • The polycyclic aromatic hydrocarbon (PAH) Network, which has operated since 1991, currently monitors the ambient concentrations of PAHs in the UK atmosphere by sampling PAHs at 31 sites across England, Wales, Scotland and Northern Ireland. (
  • This new technique was used to develop an analytical method for polycyclic aromatic hydrocarbons (PAHs), comparing the difference under reverse phase and normal phase chromatographic conditions. (
  • Polycyclic aromatic hydrocarbons (PAHs) are a group of over 100 different chemicals, typically formed during incomplete combustion, which are present in a variety of environmental matrices. (
  • The Paraíba do Sul River, in the State of Rio de Janeiro, was studied for its water quality, by determining the levels of selected polycyclic aromatic hydrocarbons (PAHs) and pesticides from six sites in two cities, Resende and Campos dos Goytacazes, as they have industrial and agricultural activities. (
  • Metabolic Activation of Polynuclear Aromatic Hydrocarbons deals with the metabolic activation of polynuclear aromatic hydrocarbons and covers topics ranging from the cytotoxic, mutagenic, and carcinogenic effects of arene oxides to the role of secondary metabolites as ultimate carcinogens. (
  • Fate of polynuclear aromatic hydrocarbons during anaerobic digest. (
  • The fate of six polynuclear aromatic hydrocarbons during anaerobic digestion of municipal sludges was investigated in a two-stage pilot-scale digester system. (
  • Polycyclic aromatic hydrocarbons, or polynuclear aromatic hydrocarbons, are a family of hydrocarbons containing two or more closed aromatic ring structures, each based on the structure of benzene . (
  • Polynuclear Aromatic Hydrocarbons, Polychlorinated Dioxins, and Dibenzofurans. (
  • However, reports on anaerobic biodegradability of polynuclear aromatic hydrocarbons (PAH) are scarce. (
  • In contrast, aliphatic hydrocarbons lack this delocalization. (
  • A most probable number (MPN) procedure was developed to separately enumerate aliphatic and aromatic hydrocarbon degrading bacteria, because most of the currently available methods are unable to distinguish between these two groups. (
  • The team used an analytical technique called tandem mass spectrometry-using an instrument provided by Lawrence Berkeley Lab and customized by Adamson-to detect gas-phase polycyclic aromatic hydrocarbons with aliphatic side chains in flames that produce soot, something never done before. (
  • One area of debate is whether the chemical byproducts in soot are polycyclic aromatic hydrocarbons, made solely out of ring-shaped groups of atoms, or contain extra, non-cyclic structures called alkyl, or aliphatic, groups. (
  • ISO 22155:2005 specifies a static headspace method for quantitative gas chromatographic determination of volatile aromatic and halogenated hydrocarbons and selected aliphatic ethers in soil. (
  • The present consideration concerns a group of 24 aliphatic, alicyclic and aromatic hydrocarbons evaluated by the JECFA (65th meeting). (
  • Chemical group 31 consists of aliphatic and aromatic hydrocarbons, of which 17 are currently authorised for use as flavours in food. (
  • Rianawati, E. and Balasubramanian, R. (2009) Optimization and Validation of Solid Phase Micro-Extraction (SPME) Method for Analysis of Polycyclic Aromatic Hydrocarbons in Rainwater and Stormwater. (
  • The new PhotoSpray source provides a sensitive ionization technique for analysis of polycyclic aromatic hydrocarbons by LC/MS/MS. (
  • Exposure to polycyclic aromatic hydrocarbons usually occurs by breathing air contaminated by wild fires or coal tar, or by eating foods that have been grilled. (
  • Human exposure to aromatic hydrocarbon metabolites induces and promotes altered DNA by mechanisms described as increased intracellular pro-oxidant production as well as direct adduction to DNA. (
  • Transplacental polycyclic aromatic hydrocarbons exposure to the fetus is compromising fetal development. (
  • A polycyclic aromatic hydrocarbon ( PAH ) is a hydrocarbon -a chemical compound containing only carbon and hydrogen-that is composed of multiple aromatic rings . (
  • Polycyclic aromatic compounds (PAH) are a very large number of naturally occurring and man-made chemicals. (
  • Sometimes there is limited substitution of halogens for the hydrogen of polycyclic aromatic hydrocarbons, in which case the larger category of chemicals is known as polycyclic aromatic compounds. (
  • Benzo(a)pyrene and other polycyclic aromatic compounds are among the diverse products of the incomplete oxidation of organic fuels, such as coal , oil, wood , and organic wastes. (
  • Consequently, polycyclic aromatic compounds can be found in the waste gases of coal- and oil-fired generating stations, steam plants, petroleum refineries, incinerators, and coking ovens. (
  • Polycyclic aromatic compounds are also present in the exhaust gases emitted from diesel and internal combustion engines of vehicles, in fumes from barbecues, in smoke from wood stoves and fireplaces, and in cigarette, cigar, and pipe smoke. (
  • Residues of polycyclic aromatic compounds are also found in burnt toast, barbecued meat, smoked fish , and other foods prepared by charring. (
  • Forest fires are an important natural source of emission of polycyclic aromatic compounds to the atmospheric environment. (
  • Because some polycyclic aromatic compounds are strongly suspected as being carcinogens, and are commonly encountered in the environment, they are considered to be an important problem in terms of toxicity potentially caused to humans. (
  • The most important human exposures to polycyclic aromatic compounds are voluntary and are associated, for example, with cigarette smoking and eating barbecued foods. (
  • However, there is also a more pervasive contamination of the atmospheric environment with polycyclic aromatic compounds, resulting from emissions from power plants, refineries, automobiles, and other sources. (
  • Both voluntary and non-voluntary exposures to polycyclic aromatic compounds are considered to be important environmental problems. (
  • Carcinogenic polycyclic aromatic hydrocarbons in umbilical cord blood of human neonates from Guiyu, China. (
  • One group of compounds typically found in exhaust, polycyclic aromatic hydrocarbons (PAH), usually occurs at very low concentrations in diesel engine exhaust. (
  • Concentrations of polycyclic aromatic hydrocarbons (PAH) were determined in the muscles and the skin of two fish species, Indian mackerel ( Rastrelliger kanagurta ) Indian scad ( Decaptens russelli ) and marine water collected from different places around the Sultanate of Oman, in February and July 1995. (
  • Concentrations of seven polycyclic aromatic hydrocarbon (PAH) compounds - benzo(a)anthracene (BaA), chrysene (CHRY), benzo(b)fluoranthene (BbF), benzo(k)fluoranthene (BkF), dibenz(a,h)anthracene (DahA), indeno(1,2,3-cd)pyrene (I123P), and benzo(a)pyrene (BaP) - in air were measured as the sum of gas and particle fractions at 32 monitoring stations dispersed across Korea during a 2-year period (February 2006 to January 2008). (
  • Atmospheric concentrations of polycyclic aromatic hydrocarbons during chimney sweeping. (
  • The seemingly unrelated human factors can best be understood by examining the role of breast tissue in aromatic hydrocarbon metabolism. (
  • [email protected]: Aromatic hydrocarbon metabolism by Rhodococcus sp. (
  • 124 was grown by batch fermentation in the presence of naphthalene and indene to measure changes in gene expression and aromatic hydrocarbon metabolism with DNA microarray technology. (
  • The combined analysis of aromatic metabolism and gene expression reveal the differential expression of multiple polycyclic aromatic hydrocarbon dioxygenases in a substrate and growth phase dependent manner. (
  • This CSEM focuses on the toxicity of polycyclic aromatic hydrocarbons. (
  • Take the Initial Check to assess your current knowledge about the toxicity of polycyclic aromatic hydrocarbons. (
  • Broccoli and its phytochemical sulforaphane activate detoxification enzymes that may protect against polycyclic aromatic hydrocarbon induced toxicity. (
  • 1.1 This test method covers the determination of total chloride (organic and inorganic) in liquid aromatic hydrocarbons and cyclohexane. (
  • ISO 7981-1:2005 specifies the determination of six selected polycyclic aromatic hydrocarbons (PAH) in drinking water. (
  • when using gas chromatography with an electron capture detector (GC-ECD), the typical limit of determination is 0,01 mg/kg to 0,2 mg/kg for volatile halogenated hydrocarbons. (
  • Determination of Polycyclic Aromatic Hydrocarbons in Wastewater, Sediments, Sludge and Plants in Karak Province, Jordan. (
  • An aromatic hydrocarbon or arene [1] (or sometimes aryl hydrocarbon ) [2] is a hydrocarbon with sigma bonds and delocalized pi electrons between carbon atoms forming a circle. (
  • One of the well-established mechanisms by which chlorinated polycyclic aromatic hydrocarbons can exert their toxic effects is via the function of the aryl hydrocarbon receptor (AhR). (
  • Aryl Hydrocarbon Receptor (AhR) is a cytosolic, ligand-activated transcription receptor. (
  • Resveratrol may repress aryl hydrocarbon receptor activity in cancer cell lines. (
  • Activation of the cell death pathway in immature follicles of exposed females was mediated by the aryl hydrocarbon receptor (Ahr), as ovarian reserve was fully rescued by maternal cotreatment with the Ahr antagonist, resveratrol, or by inactivation of the Ahr gene. (
  • They are structurally similar to other halogenated hydrocarbons such as polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), and polychlorinated biphenyls (PCBs). (
  • DNA reactions, mutagenic action and stealth properties of polycyclic aromatic hydrocarbon carcinogens [review]. (
  • Benzo[a]pyrene (BaP), a key polycyclic aromatic hydrocarbon (PAH) often associated with soot particles coated by organic compounds, is a known carcinogen and mutagen. (
  • Polycyclic aromatic hydrocarbons are a class of organic compounds having two or more fused benzene rings. (
  • The EU-RL for polycyclic aromatic hydrocarbons in Feed and Food as laid down in Regulation (EU) 2017/625 contributes to the implementation of high quality implementation and uniform results. (
  • The effect of aromatic hydrocarbons composition on particulate emissions is also investigated by considering the same amount of global aromatic hydrocarbons but different aromatic composition: heavy aromatic hydrocarbons (C11)- and light aromatic hydrocarbons (C7-C9). (
  • Results illustrate a good correlation between particulate emissions and aromatic hydrocarbons content but little or no sensitivity of particulate emissions to ethanol content in the fuels. (
  • It was also found that particulate emissions present a high sensitivity to heavy aromatic hydrocarbons content. (
  • These results highlight the importance of fuel quality and more specifically the role of heavy aromatic hydrocarbons on particulate emissions. (
  • Samples of suspended particulate matter, collected at four sites in Zagreb during the heating season were analysed for the content of polycyclic aromatic hydrocarbons. (
  • In aromatic substitution one substituent on the arene ring, usually hydrogen, is replaced by another substituent. (
  • While usually referring to compounds made of carbon and hydrogen , PAH also may include fused aromatic compounds containing nitrogen , sulfur, or cyclopentene rings. (
  • Through-space isotropic NMR shielding values of a perpendicular diatomic hydrogen probe moved in a 0.5 Å grid 2.5 Å above several polycyclic aromatic/antiaromatic ring and aromatic/aromatic hydrocarbons were computed with Gaussian 03 at the GIAO HF/6-31G(d,p) level. (
  • Methane is the simplest hydrocarbon, consisting of one carbon atom and four hydrogen atoms. (
  • A polycyclic aromatic hydrocarbon ( PAH ) is a hydrocarbon (i.e., compound of hydrogen and carbon ), more specifically, an aromatic hydrocarbon (including a ring), arranged in benzene rings (rings of six joined carbon atoms) interconnected like chickenwire (fence material of wire joined forming similar six-sided shapes). (
  • Air sampled from the breathing zone of chimney sweeps during "dirty work" and soot samples were analysed for polycyclic aromatic hydrocarbons (PAH). (
  • Sandia National Laboratories scientists Scott Skeen, left, Nils Hansen, center, and Brian Adamson discuss tandem mass spectrometry, which was used for the detection of aliphatically linked polycyclic aromatic hydrocarbons found in soot producing flames. (
  • The newly recognized compounds can be used to create more detailed models of combustion that, in turn, can help in the design of cleaner, more efficient engines that emit less soot and fewer harmful hydrocarbons into the atmosphere. (
  • Recent work by Sandia scientist Hope Michelsen, technologist Paul Schrader and former postdoctoral researcher Olof Johansson broke ground by identifying chemical chain-reaction processes where hydrocarbons could form soot. (
  • The configuration of six carbon atoms in aromatic compounds is known as a benzene ring, after the simplest possible such hydrocarbon, benzene . (
  • Here we report that adding organic ligands that bind to Fe(III) dramatically increases its bioavailability, and that in the presence of these ligands, rates of degradation of aromatic hydrocarbons in anoxic aquifer sediments are comparable to those in oxic sediments. (
  • Harvey, R. G. Polycyclic Aromatic Hydrocarbons: Chemistry and Carcinogenicity . (
  • The simplest of such chemicals are naphthalene , having two aromatic rings, and the three-ring compounds anthracene and phenanthrene . (
  • Benzene-substructure resonance analysis for Clar's rule Phenanthrene Anthracene Chrysene For example, phenanthrene has two Clar structures: one with just one aromatic sextet (the middle ring), and the other with two (the first and third rings). (
  • Fanick, E. and Kroll, S., "Polycyclic Aromatic Hydrocarbons in Diesel Engine Exhaust Both with and without Aftertreatment," SAE Technical Paper 2018-01-1812, 2018, . (
  • In the dissolved fraction, 41 polycyclic aromatic hydrocarbons and their derivates were quantified, among them are 16 EPA priority pollutants. (
  • This book begins with a brief review of the early work on the mechanism of chemical carcinogenesis by polynuclear hydrocarbons, followed by a detailed survey of pertinent literature in the field. (
  • Aromatic hydrocarbons benzene, toluene, ethylbenzene, and isomeric xylenes (BTEX) are volatile organic compounds widespread in the biosphere because of their physical and chemical properties and their use. (
  • They are unsaturated hexagonal ring structures with a closed conjugated system of double bonds that gives them the characteristic chemical properties of the parent aromatic hydrocarbon , benzene . (
  • Chemical and Ecotoxicological Assessment of Selected Biologically Activated Sorbents for Treating Wastewater Polluted with Petroleum Products with Special Emphasis on Polycyclic Aromatic Hydrocarbons. (
  • Therefore, in this molecule the outer rings have greater aromatic character whereas the central ring is less aromatic and therefore more reactive. (
  • An aromatic molecule is one which forms a benzene ring. (
  • Mean levels of major aromatic and chlorinated hydrocarbons were higher indoor (platforms and mezzanines) than outdoor with average indoor/outdoor (I/O) ratios of 1.1-9.5, whereas no significant indoor/outdoor differences were found except for benzene and TrCE. (
  • The major aromatic products from the oxidation of the xylenes were the isomeric tolualdehydes, toluene and a-xylylcne oxide (from a-xylene). (
  • Benzene , C 6 H 6 , is the simplest aromatic hydrocarbon, and it was the first one named as such. (
  • Chlorella works for polycyclic aromatic hydrocarbon detoxification through the epigenetic modulation. (
  • Although experimental breast cancer may be induced by estrogenic hormones, X-radiation and aromatic hydrocarbons, only aromatic hydrocarbons have not been previously implicated in human mammary carcinogenesis. (
  • If correct, the hypothesis would account for some of the increase in breast cancer incidence in industrial countries--and would suggest environmental and dietary modifications that would inhibit hydrocarbon induced mammary carcinogenesis. (
  • Sulforaphane inhibit polycyclic aromatic hydrocarbon-induced enzyme induction associated with carcinogenesis. (
  • The mechanism of binding of metabolites derived from polynuclear hydrocarbons to key cellular sites is also discussed. (
  • The breast is anatomically embedded in a major fat depot which stores and concentrates aromatic hydrocarbons and can metabolize these hydrocarbons to carcinogenic metabolites. (
  • For references , please go to or scan the QR code. (
  • Aromatic hydrocarbons are important environmental chemicals produced by the incomplete combustion of hydrocarbons for use in energy production. (
  • Zhang, P. & Chen, Y. G. Polycyclic aromatic hydrocarbons contamination in surface soil of China: a review. (
  • 124 is a Gram-positive soil bacterium being developed for the manufacture of (-)cis-(1S,2R)-1-aminoindan-2-ol, a key precursor in the production of the HIV-1 protease inhibitor CrixivanTM, from the aromatic hydrocarbon indene. (
  • Contamination of ground waters with water-soluble aromatic hydrocarbons, common components of petroleum pollution, often produces anoxic conditions under which microbial degradation of the aromatics is slow. (
  • Our results suggest that increasing the bioavailability of Fe(III) by adding suitable ligands provides a potential alternative to oxygen addition for the bioremediation of petroleum-contaminated aquifers.Contamination of ground waters with water-soluble aromatic hydrocarbons, common components of petroleum pollution, often produces anoxic conditions under which microbial degradation of the aromatics is slow. (
  • Could saponins be used to enhance bioremediation of polycyclic aromatic hydrocarbons in aged-contaminated soils. (
  • Polycyclic aromatic hydrocarbons (PAH) are naturally occurring compounds found in the environment. (
  • A flame that was sampled by Sandia National Laboratories scientists against the backdrop of mass spectra and polycyclic aromatic hydrocarbon compounds found inside the flame. (
  • Chlorinated polycyclic aromatic hydrocarbons are generated by combustion of organic compounds. (
  • These hydrocarbon chains can make the links among polycyclic aromatic hydrocarbons more stable at the high temperatures of combustion, greater than 3,600 degrees Fahrenheit. (
  • No comments were found for Sorption of polycyclic aromatic hydrocarbons to polystyrene nanoplastic . (
  • Examples of non-benzene compounds with aromatic properties are furan , a heterocyclic compound with a five-membered ring that includes a single oxygen atom, and pyridine , a heterocyclic compound with a six-membered ring containing one nitrogen atom. (
  • The terms polyaromatic hydrocarbon [1] or polynuclear aromatic hydrocarbon [2] are also used for this concept. (
  • A polyaromatic hydrocarbon may have rings of various sizes, including some that are not aromatic. (
  • Many people think that all aromatic molecules contain one or more benzene rings. (
  • Benzene rings are found in many, but not all aromatic molecules. (
  • So, it is a common misconception that all aromatic molecules contain benzene rings. (
  • group of organic compounds t wo or more aromatic (benzene) rings are fused together. (
  • Monoaromatic hydrocarbons, such as toluene and benzene, have been shown to undergo microbial degradation in the absence of oxygen, and even to serve as microbial growth substrates under those conditions. (
  • To help determine if this is detrimental to the surrounding environment, more information is needed on the extent and pattern of creosote, or more specifically polycyclic aromatic hydrocarbon (PAH), migration from railroad ties and what effects this would have on the surrounding environment. (
  • Taking 1.5 as a borderline value for the BghiPer/BaP ratio, a significant influence of car traffic on air pollution by polycyclic aromatic hydrocarbons was noticed at a site close to a petrol station. (
  • One of the alterations in property, which occurs together with desirable changes, is that of insolubilization in common hydrocarbon solvents. (
  • C9 aromatic hydrocarbon resin is a petroleum by-product of pyrolysis C9 fraction which is produced by pre-treatment, polymerization and distillation processes. (